Hello,
Take my apologies for the delay in answering.
I just enabled JS optimization in the cache plugin settings https://prnt.sc/1qaem2b
Disabling of these options only slows down the score. I suppose that you had a better result before our changes because you have JS error that did not allow normal loading of the images and other elements, so the page was almost empty and that’s why a good score was there. But once the page loading all the elements that it should then the score is slower.
You may try the NitroPack plugin to get better google speed and GTmetrix results.
Regards