Frame Rate Substitution Error

Hello

I’ve been getting these frame substitution and error retrieving messages on my Premiere Pro. 
My Premiere Pro version is 25.6.2. The footage is the A-roll, which I cannot remove and which has never before troubled me. I’ve tried deleting the cache, creating a separate sequence, and restarting Premiere Pro, but nothing works.
Is there a way to solve this problem? 
Updated it to 26.0;

still doesn’t work.

Attaching a screenshot

Please help

Thanks