linux – External HDD unexpected failure

Today I connected my external HDD to transfer a file. Everything seemed to be working fine – it wasn’t slow, all files were showing up. In the middle of transfer of the new file, it suddenly disconnected and I haven’t been able to connect it back.

dmesg:

(  947.713433) sd 6:0:0:0: Attached scsi generic sg2 type 0
(  947.713647) ses 6:0:0:1: Attached Enclosure device
(  947.713937) ses 6:0:0:1: Attached scsi generic sg3 type 13
(  947.714589) ses 6:0:0:1: Failed to get diagnostic page 0x1
(  947.714616) ses 6:0:0:1: Failed to bind enclosure -19
(  947.715864) sd 6:0:0:0: (sdb) Spinning up disk...
...
...
(  982.772209) sd 6:0:0:0: (sdb) No Caching mode page found
(  982.772218) sd 6:0:0:0: (sdb) Assuming drive cache: write through
( 1015.039086) ldm_validate_partition_table(): Disk read failed.
( 1015.039128) Dev sdb: unable to read RDB block 0
( 1015.039188)  sdb: unable to read partition table
( 1015.041932) sd 6:0:0:0: (sdb) Attached SCSI disk
( 1015.047915) scsi_io_completion: 3688 callbacks suppressed
( 1015.047922) sd 6:0:0:0: (sdb) tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
( 1015.047927) sd 6:0:0:0: (sdb) tag#0 Sense Key : Not Ready (current) 
( 1015.047931) sd 6:0:0:0: (sdb) tag#0 Add. Sense: Medium not present
( 1015.047935) sd 6:0:0:0: (sdb) tag#0 CDB: Read(10) 28 00 3a 37 5f 80 00 00 08 00
( 1015.047937) print_req_error: 3688 callbacks suppressed
( 1015.047939) print_req_error: I/O error, dev sdb, sector 976707456

smartctl:

=== START OF INFORMATION SECTION ===
Model Family:     Western Digital Black
Device Model:     WDC WD3200BEKT-75PVMT1
Serial Number:    WD-WX51A33L6540
LU WWN Device Id: 5 0014ee 6ae08eefd
Firmware Version: 01.01A01
User Capacity:    320,072,933,376 bytes (320 GB)
Sector Size:      512 bytes logical/physical
Rotation Rate:    7200 rpm
Device is:        In smartctl database (for details use: -P show)
ATA Version is:   ATA8-ACS (minor revision not indicated)
SATA Version is:  SATA 2.6, 3.0 Gb/s
Local Time is:    Wed Dec 30 14:10:00 2020 PST
SMART support is: Available - device has SMART capability.
SMART support is: Enabled

=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED

General SMART Values:
Offline data collection status:  (0x00) Offline data collection activity
                    was never started.
                    Auto Offline Data Collection: Disabled.
Self-test execution status:      (   0) The previous self-test routine completed
                    without error or no self-test has ever 
                    been run.
Total time to complete Offline 
data collection:        ( 5880) seconds.
Offline data collection
capabilities:            (0x7b) SMART execute Offline immediate.
                    Auto Offline data collection on/off support.
                    Suspend Offline collection upon new
                    command.
                    Offline surface scan supported.
                    Self-test supported.
                    Conveyance Self-test supported.
                    Selective Self-test supported.
SMART capabilities:            (0x0003) Saves SMART data before entering
                    power-saving mode.
                    Supports SMART auto save timer.
Error logging capability:        (0x01) Error logging supported.
                    General Purpose Logging supported.
Short self-test routine 
recommended polling time:    (   2) minutes.
Extended self-test routine
recommended polling time:    (  61) minutes.
Conveyance self-test routine
recommended polling time:    (   5) minutes.
SCT capabilities:          (0x7035) SCT Status supported.
                    SCT Feature Control supported.
                    SCT Data Table supported.

SMART Attributes Data Structure revision number: 16
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
  1 Raw_Read_Error_Rate     0x002f   200   200   051    Pre-fail  Always       -       0
  3 Spin_Up_Time            0x0027   159   136   021    Pre-fail  Always       -       1025
  4 Start_Stop_Count        0x0032   099   099   000    Old_age   Always       -       1142
  5 Reallocated_Sector_Ct   0x0033   200   200   140    Pre-fail  Always       -       0
  7 Seek_Error_Rate         0x002e   100   253   000    Old_age   Always       -       0
  9 Power_On_Hours          0x0032   098   098   000    Old_age   Always       -       2095
 10 Spin_Retry_Count        0x0032   100   100   000    Old_age   Always       -       0
 11 Calibration_Retry_Count 0x0032   100   100   000    Old_age   Always       -       0
 12 Power_Cycle_Count       0x0032   099   099   000    Old_age   Always       -       1107
191 G-Sense_Error_Rate      0x0032   001   001   000    Old_age   Always       -       601
192 Power-Off_Retract_Count 0x0032   200   200   000    Old_age   Always       -       78
193 Load_Cycle_Count        0x0032   178   178   000    Old_age   Always       -       67059
194 Temperature_Celsius     0x0022   101   063   000    Old_age   Always       -       42
196 Reallocated_Event_Count 0x0032   200   200   000    Old_age   Always       -       0
197 Current_Pending_Sector  0x0032   200   200   000    Old_age   Always       -       0
198 Offline_Uncorrectable   0x0030   100   253   000    Old_age   Offline      -       0
199 UDMA_CRC_Error_Count    0x0032   200   200   000    Old_age   Always       -       0
200 Multi_Zone_Error_Rate   0x0008   100   253   000    Old_age   Offline      -       0
240 Head_Flying_Hours       0x0032   098   098   000    Old_age   Always       -       1897
241 Total_LBAs_Written      0x0032   200   200   000    Old_age   Always       -       2423437807
242 Total_LBAs_Read         0x0032   200   200   000    Old_age   Always       -       1617390794
254 Free_Fall_Sensor        0x0032   195   195   000    Old_age   Always       -       5

SMART Error Log Version: 1
No Errors Logged

SMART Self-test log structure revision number 1
Num  Test_Description    Status                  Remaining  LifeTime(hours)  LBA_of_first_error
# 1  Short offline       Completed without error       00%         0         -

SMART Selective self-test log data structure revision number 1
 SPAN  MIN_LBA  MAX_LBA  CURRENT_TEST_STATUS
    1        0        0  Not_testing
    2        0        0  Not_testing
    3        0        0  Not_testing
    4        0        0  Not_testing
    5        0        0  Not_testing
Selective self-test flags (0x0):
  After scanning selected spans, do NOT read-scan remainder of disk.
If Selective self-test is pending on power-up, resume after 0 minute delay.

I believe there are no errors in smartctl and lsblk shows it up as well. I tried running testdisk and it showed me that no partition is available. I didn’t run a deep scan as I haven’t created a backup image yet and don’t want to mess with it.
Whenever I connect it to a Windows machine it appears in the Device manager, without any warnings, but it’s not visible and can’t be opened.

What could be the problem here?