Can i find out who keeps spoof calling me?

the other day some random number called me.. i didn't answer but ended up calling back a few minutes later... welllllll it was my ex boyfriend's number... i asked him why he had called me, of course, he said he didn't... then handed the phone to his soon to be wife... we got into a fight because she said he didn't call but I had proof he just had... she hangs up on me and then his number calls me again... i picked up, asked why they were calling again, and a weird voice says "hey"... i ask who it was.. they reply "who do you want it to be"... i hang up and called back my ex's phone... his girlfriend and i figured out someone was using an application where you can put in another number and it won't show who is really calling... i guess its called a spoof app... i checked my phone records online but it shows his number not the prank caller's number... is there some other way of figuring out who really called... his girlfriend and I would love to know who's trying to start problems between her, our boyfriends, and I... thanks to all who answer this serious!