How should i maintain my crossbow?

i put wax on the string to prevent extensive friction, so i have that covered. i re-screw the screws in when they become loose. my main question is, do i have to oil the trigger assembly? today while shooting in this 80 degree hot weather, my trigger got somewhat jammed. when i took my shot, the trigger stayed back. i had to push it forward so that i could get the next shot. it wasn't stuck extensively but i'm still a little worried. so should i lube it to maintain it? or is it fine if i don't?