I've hit the wall every now and then from: too many injuries, too much work, too many other things to do and playing with people that are too serious or predictable or too many people. .period...
Time off helps but you need to remember what it is that you like. Play an early morning solo round with a fun set, say 165 Roadrunner, Atom and ... I can't remember, insert one of your mids here.... Comet? Something that is just fun and easy to throw. Dump your bag and some backups in a pillow case and pick 5. Or play with a random group or less experienced but enthusiastic friend, or a buddy that brings good tunes and a few beer.
I love it on quiet morning before work when the sun is low, even if I just play the bottom 5 loop (flat, easy, 160' ish) or play it backwards.
Eat well, drink lots of water, take lots of snacks and don't forget your towel or seat. Throw a hundred practice putts in the next couple days but don't wear yourself out, just prep enough for some confidence. Practice at a range where you hit 2 out of three or better.
Do what you do and don't worry about it, play the tournament for fun and socialization, play smart and cool and just take your pars. It sounds like there's no pressure for you it might be a casual round, that's when I play my best.