I paused Pathfinder right at the end of a long dungeon before a boss, and every time I try to pick it up again I find that I've forgotten the combat mechanics and am unable to beat the boss, become demoralized and quit again.
I keep half-heartedly coming back to it because I (now dimly) remember really enjoying the game, although at this point I've pretty much totally forgotten where I was in the plot. But … it's too long to start again!
There are different ways to come back there. One is to read the journal, starting with the main quest, then the companion and side quests. It usually does it for me, what was I doing when I left?
For the mechanics, you could reload a slightly older game to avoid the pressure of an important opponent to beat. Once things get back in place, come back to where you were. But first, make sure to save the last game with a named save, since there is a limited number of quick saves (it would be a shame to overwrite it)
Or switch to turn-based mode for a while, so you can take the time which each character, before going back to real-time with pause.
I chose a spell, started the round by unpausing and - nothing happened. So the game obviously allowed me to choose a spell, which would not work in this situation, but gave me no indication why. I assume the enemy I wanted to use the spell on was too far away. But in such case I had expected that either the game had indicated me the range of my spell (like in TOEE) in advance or had prevented me from choosing it on this enemy at all, like some other games, or that it would make my character run nearer to the enemy and then use the spell (possible needing more than one round, of course). But none of these variants happened, my avatar simply did nothing at all, while the enemy and the companion all did their turn. Other actions like Melee, ranged weapons etc. seemed to work like expected and I could have played on using these but I didn't want to.
The devil is in the details, read carefully the spell, or check in the Core Rulebook if you have it, if not on
https://www.d20pfsrd.com/. I had a few misses because the spell only applied to humanoids, for example, wouldn't work on other monsters. Sometimes not all details are shown on the spell tooltip, so I look in the book to make sure.
When a spell doesn't apply to a target, the spell icon under your mouse cursor should be barred, I think. Or the character says something along the lines of "I can't do it".
I assume there was nothing in the logs? Every miss that is roll-related should appear there.
There is an option to show what action characters are preparing, with a little icon over their heads (option to show it when hovering, always, never, and so on). I found that helpful to make sure my casters were actually preparing their spells.
If you don't find out, if some part of the mechanics is not clear, don't hesitate to ask in their forums (or on Discord), there are always people eager to help, and they generally know the rules inside out.
