Sorry for your issue. I suggest you can send your log file to us and we will check it. If this could not help us solve your problem, we are also glad to provide remote support.
Hey, I had a similar issue with DLSS 3.0 after updating to version 2.5. What worked for me was doing a clean driver uninstall using DDU and then reinstalling driver version 536.67 fresh. Also make sure Windows Game Mode is turned on because frame generation needs that.
But here is something else I learned the hard way. Sometimes the problem is not your settings at all. It could be that a background app or a small glitch is blocking the feature. I had a friend who could not figure out why his frame gen was missing, so I used a free tool called UltraViewer to take control of his PC and look around myself. Turns out his Nvidia control panel had a weird profile locked in. Being able to see his screen directly saved us hours of back-and-forth texts.
Hope you get it fixed soon. Let me know if the clean driver install works for you.