java – Why I can’t Install openjdk-8 in linux system?

I am trying to install openjdk 8 but its say that unable to locate package openjdk 8. Currenty openjdk 16 is installed & activated in my system and I installed openjdk 11 without any error but I am not able to install openjdk 8.

sudo apt install openjdk-8-jdk
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
E: Unable to locate package openjdk-8-jdk