Hey hi Edmond, looks like your screen is already a defective one. Try replacing your screen, have a look at this.
=== [product|IF356-229|Google Pixel 5 Screen - Genuine|new_window=true] [product|IF356-229|(THIS IS A LINK)|new_window=true] ===
=== [guide|140507|Google Pixel 5 Screen Replacement|new_window=true] [guide|140507|(THIS IS A LINK)|new_window=true] ===
You should return the screen you have right now (if possible), and get the official iFixit genuine screen.
I hope this helps you out and please let me know if this does not help, please let me know =)