Ex's fighting over baby...HELP

So my ex's are fighting over who the dad is to my unborn baby. (No I was not sleeping with them at the same time)

My ex fiance and I had sex September 24th nothing after that. (We were not together but just sleeping together)

My ex boyfriend and I had sex September 30th, October 4,11,16&17.

I missed my period October 20th-25th a week later I took a home test cause was about 2 weeks late and it came back positive.

I am now 12 weeks pregnant which means I got pregnant about the 17th or so being they add the 2 weeks on which would make it the 2nd.

Which one is most likely the father ex fiance or ex boyfriend???

*PLEASE NO RUDE COMMENTS!!*

I am sure I know who the father is but one of them can't accept it so I want to know what yall think.