Grub failed boot detection

[mahesh]

Hi fnds...

I am new to Ubuntu. And install latest version of Ubuntu 22.04. it was successfully installed. After that I install proton vpn, last step I mistakenly changed the desktop environment so that affect my laptop graphics driver . Screen shows bigger... After that I do many way to try my laptop normal but I am very tired. So I reinstall again Ubuntu. After successful installation, laptop stuck on black screen with underline blinking... I know this is boot failure. ... Grub not loading well..

I saw many videos and try that methods, but none of the methods was working.... Then I install previous version of Ubuntu 20.04 then it was fine... After I upgrading my Ubuntu to latest version. Again that issue came.. grub failed boot detection.... Then I walkover from Ubuntu..... Now I am using zorin os.... But I like Ubuntu very much... Please give any solution to solve this issue.....