Failed to find Build Tools revision 29.0.0 - Android Builds

Now from my all Android projects, I can't able to export Android builds after updating library using Android Studio. I was, again and again, getting the same error:



This project does not contain any kind of external plugins installed. Then also I was getting this error, just two days before it was working properly.

 

I had similar problems, managed to solve it, but now my app crashes (it might be something else).

In Player Settings / Publishing Settings/ Build check Custom Gradle Template.

After that edit the file in Unity's folder:
in my case its:
/Applications/Unity/Hub/Editor/2018.3.10f1/PlaybackEngines/AndroidPlayer/Tools/GradleTemplates.

Here are 2 files: mainTemplate.gradle and libTemplate.gradle.
Create backups.

In them there are template variables, what I done is altered the '**BUILDTOOLS**' to '29.0.0 rc2', because I have this version installed via Android Studio.

It took me a couple of hours to solve that.
I hope it helps.

 

This solution worked for me:
https://stackoverflow.com/questions...5499494?noredirect=1#comment97709905_55499494