EF 70-200mm f/2.8L IS III USM on a R5, R6 and a 5DM3 lost the ability to focus.

[Walt1]

I was getting a err1 code on my R5 when I was using my EF 70-200mm f/2.8L IS III USM lens and cleaned the contacts with an eraser and a cloth now the lens will not focus, I borrowed a version 2 of same lens but that will not focus on any of the cameras as well. But if I put my version 1 lens on any of the cameras it works just fine.  I am using a canon EF-EOS adaptor new and old and same results with both.  Is there anything I can do before I ship everything to Canon service and take out a home loan to pay for it all? lol

[deebatman316]

Does the camera report the aperture that is set or does it say F/-- or F/00 for the 70-200mm F/2.8 IS MK II and MK III versions. When you say the version 1 lens do you mean the original non-IS version or the 1st gen IS model. What happens if you try the affected lenses on an EF Mount camera. Do they work correctly on that camera or does it report F/-- or F/00.