I don't know if you've noticed but for some threads, if they were created more than one year ago and had some unknown time of inactivity, they can't be bumped onto the "recently active" list. I was wondering if this could be fixed, I put some examples below.

ktt2.com/caroline-polachek-thread-1327

ktt2.com/clairo-thread-immunity-out-now-1279

pretty sure this is by design.

some threads op can bump them tho

This is by design as the person above said. E.g. the first thread says "clairo immunity out now". You should create a new thread.