I believe my account has been hacked so what do I do now!

I’m pretty positive a boyfriend has got into my entire phone and somehow.. I’ve changed password an Apple ID 2 times but he is a android kinda guy but apparently a wiz at hacking into things .. Google , emails , Apple ID calls & text , Snapchat messenger and Even ID me account!’ How is it possible and wtf do I do to block his *** from apple.Id and everything else.. I believe he is using imei # and sim information then he’s in it , least that’s what I’ve gathered from him talking about how his buddy could hacked in the white house and dark web stuff… what can I do besides get another phone cause I already done that in which I believe he’s already got it to… nothing to hide at all but I’m not invading his privacy so why should he be all up in my personal life