black screen, I only hear sound

THIS IS THE FIRST TIME I HAVE ENCOUNTERED THIS PROBLEM.
After using the modify function and changing the color space of the files. The source files in the folders, as well as the main sequence, turned black. When playing, I only hear audio, but the video is not displayed. At the same time, everything works fine inside the nested sequence. How to solve this problem? P.S. Premier Pro 2024 lags a lot and works slowly, it is impossible to use it. And the beta version, on the contrary, works fine except for this problem, which I encountered for the first time