postfix – Posftwd is double counting emails when used with Posftix and amavis

Our Postfix mail server uses Amavis with spam assassin for spam and virus scanning. We have it setup in a way , postfix forwards mail to amavis and amavis then re queue the email back to postfix to sending it to destination.
I have setup postfwd with a simple rule to reject emails after a threshold for sender but Postfwd is double counting the emails. When I send one email through Outlook as a mail client, Postfwd is counting it as two instead. Im new with SMTP protocols and is struggling to pin point the issue. If anyone could please help. I have pasted some configuration snippets which I think will be useful below.

Below is an output for postconf -n

append_dot_mydomain = no
biff = no
broken_sasl_auth_clients = yes
content_filter = amavis:(
disable_vrfy_command = yes
dovecot_destination_recipient_limit = 1
enable_original_recipient = no
header_checks = regexp:/etc/postfix/header_checks
inet_interfaces = all
mailbox_size_limit = 0
maximal_backoff_time = 8000s
maximal_queue_lifetime = 7d
minimal_backoff_time = 1000s
mydestination = $myhostname
myhostname = pXXX
mynetworks = (::ffff: (::1)/128,XXX
mynetworks_style = host
myorigin = /etc/hostname
readme_directory = no
recipient_delimiter = +
relay_domains = hash:/etc/postfix/relay_recipients
smtp_enforce_tls = no
smtp_helo_timeout = 60s
smtp_tls_note_starttls_offer = yes
smtp_tls_security_level = may
smtp_use_tls = yes
smtpd_banner = $myhostname ESMTP $mail_name
smtpd_client_connection_count_limit = 30
smtpd_client_recipient_rate_limit = 300
smtpd_client_restrictions = permit_mynetworks, permit_sasl_authenticated, check_client_access hash:/etc/postfix/whitelist, reject_rbl_client
smtpd_data_restrictions = reject_unauth_pipelining
smtpd_delay_reject = yes
smtpd_enforce_tls = no
smtpd_hard_error_limit = 12
smtpd_helo_required = yes
smtpd_helo_restrictions = check_client_access hash:/etc/postfix/whitelist, permit_mynetworks, warn_if_reject reject_non_fqdn_hostname, reject_invalid_hostname
smtpd_recipient_limit = 30
smtpd_recipient_restrictions = reject_unauth_pipelining, check_policy_service inet:, permit_mynetworks, permit_sasl_authenticated, reject_non_fqdn_recipient, reject_unknown_recipient_domain, reject_unauth_destination, check_policy_service inet:
smtpd_relay_restrictions = permit_mynetworks, check_client_access hash:/etc/postfix/whitelist, check_sender_access hash:/etc/postfix/whitelist, permit_sasl_authenticated, reject_non_fqdn_recipient, reject_unknown_recipient_domain, reject_unauth_destination, check_policy_service inet:
smtpd_sasl_auth_enable = yes
smtpd_sasl_authenticated_header = yes
smtpd_sasl_local_domain =
smtpd_sasl_path = private/auth
smtpd_sasl_type = dovecot
smtpd_sender_restrictions = check_sender_access hash:/etc/postfix/sender_access, permit_sasl_authenticated, permit_mynetworks, reject_unknown_sender_domain, reject_unauth_pipelining, warn_if_reject reject_sender_login_mismatch, warn_if_reject reject_non_fqdn_sender, warn_if_reject reject_unlisted_sender, warn_if_reject reject_non_fqdn_sender
smtpd_soft_error_limit = 3
smtpd_tls_cert_file = XXX
smtpd_tls_key_file = XXX
smtpd_tls_loglevel = 1
smtpd_tls_received_header = yes
smtpd_tls_security_level = may
smtpd_tls_session_cache_timeout = 3600s
smtpd_use_tls = yes
tls_random_source = dev:/dev/urandom
transport_maps = hash:/etc/postfix/transport
unknown_local_recipient_reject_code = 450
virtual_alias_maps = proxy:mysql:/etc/postfix/, proxy:mysql:/etc/postfix/
virtual_gid_maps = static:125
virtual_mailbox_base = /home/vmail
virtual_mailbox_domains = proxy:mysql:/etc/postfix/
virtual_mailbox_maps = proxy:mysql:/etc/postfix/, proxy:mysql:/etc/postfix/
virtual_transport = dovecot
virtual_uid_maps = static:150

Postfwd rules:

id=20perminute; sender=~/; action=rate(sender/20/60/REJECT only 20 messages per minute for $$sender)

Anyone able to help throw some light into this issue?