Car battery issues(?)/car not starting

My 2002 Honda CR-V did nothing when I tried to start it about a month ago (no lights, no reaction at all) but jumping it worked. I assumed I had just left my lights on or something, but then it happened again. I jumped it again, figured I just needed a new battery (old one was about 4 yrs old) but when I went to go get a new battery, car wouldn’t start at all and jumping it didn’t work. I installed a new battery and the car started a number of times with no issue, I assumed the problem had been solved. But now the same thing just happened with the new battery. Jumping the car worked, but if it was a battery issue, why would that happen with a brand new battery? Anyone have any thoughts? Not sure what’s up here