Google Photos did not compress a few items, even on high quality mode

As the title suggests,

1. My settings on my Android app is high quality, not original size


2. Most photos are getting compressed, very few photos are left uncompressed


3. Most videos are left uncompressed


4. The uncompressed items aren't eating into my Google Drive space


5. For checking, I uploaded with these individual files on another test Google account and found out that they are getting compressed.

I want all items to get compressed since it's the algorithm is best of both worlds - retains 99.99% quality and reduces space by >50%.

I can't delete these items from the cloud since that would immediately delete it from my phone, not allowing another attempt of uploading. What can be done to compress these missed items?