u/DefinitionAdvanced39

As the title suggests, I'd like some advice on how I can bring back some enjoyment for myself in my campaign. It's been a long-time running, due to frequent scheduling issues, which are pretty inevitable but not the issue here.
My two primary issues are the following: firstly, players ruining RP moments with constant jokes, with a lot of crude jokes. Secondly, despite having played for a few years and players being mid-levels, players not knowing what their characters can do. Thirdly, note-taking/paying attention to the story.
For the first point, we all have a similar sense of humour, and there's a dedicated meme channel for us all. What is becoming increasingly frustrating is when players will interrupt RP verbally with jokes and therefore get rid of the seriousness of the moment. I've frequently tried to continue but it's got rid of the emotions I would like to be portrayed.
For the second, I'm sure that I have mentioned this plenty of times to drill the point home, and have often suggested to the players what they could possibly do in the moment. However, with higher-level enemies, or large groups of enemies, there's only so much that I can manage in combat, and I think it's becoming evident that it's frustrating to me, yet things haven't changed.
Finally, as mentioned, absences happen and can't be avoided. For those who can't make the session, we implemented at the very beginning of the campaign a group note channel. Players take it in turns to write the notes for that session (and at least two of them take their own personal notes). What has become evident recently is there are players who don't even bother. This was made obvious when we were into session 10 of the most recent arc and one of the players asked why we were putting in all this effort for a silly side quest...
I'm starting to become a bit put off from it all, but don't want to end a campaign half-finished. Any advice would be much appreciated, and I'm very open to any criticism too! Anything that will improve the game!