Cover photo when changed is duplicated in feeds.

Hi.

Can anyone tell me how I can correct this mistake with a duplicate notification that someone has already described here? https://github.com/PHPfox-Official/phpfox-v4-issues/issues/2240
I also have such a mistake.
I waited a month for version 4.6.1 to exit, hoping that you would fix bugs from version 4.6.0. I've already paid programmers for modifications to the script, but they can't start working because new bugs appeared.
You can tell me how I can fix it myself (what and where to fix it) in order to fix the error?
Should I wait another 2-3 months for you to make an amendment?
I'm sorry, but I'm angry because I've paid a lot of money for something that doesn't work properly. I understand that this is a mistake, but you are correcting some mistakes and making more mistakes. 
I don't know what to do now, because a script with such an error will disturb users...

If You can, please help me.

Thank you.