Colors In PREMIERE PRO 2021 renders Have become noticeably duller a week after using.

I am a musician who has made my own music videos. I rent adobe. I thought I was done a week ago. The videos all rendered exactly as bright and colorful as they appeared inside the program. A week later I have discovered that the compression that YouTube adds to music videos really strangles the audio. I used 16BIT 48K music last week. This week I am using 24bit 96k WAV files in Premiere. This sounds much better on YouTube even after they compress on upload.

However, now all the colors look dull on the videos. desaturated. I have not updated anything. I have looked at the old videos and new side by side and it is very noticeable.

My computer is a 2011 Mac so I am stuck at Adobe 2021 (My OS etc have all stayed the same). So.... Nothing on my end has changed. I paid for another moth of Premiere Pro. Do they change anything when you renew a membership. My version is 15.4.5 which is 2021.

I made zero changes to the video side of the files. I simply opened them, added a WAV file for the music and rerendered. The result is a dull looking render with music that has a much higher dynamic range. But the colors a week ago looked SO good!

What can I do? Please help!