How to set missing serial number on MacBook Pro 2014

My MacBook pro model 2014 mid 15 inches, has lost serial number during upgrading the OS. I am having Catalina Os installed on the machine and have tried with a guide that tells about the Blank board serializer I write it to USB drive and when boot up the machine, Clicked EFI BOOT start normally nothing effect. All I want any other way of setting back my serial number. I am struggling for the last one month to fix the issue please help me out.