Ok so I have a bit of a situation that I would really appreciate some insight on

Approximately 2 months ago my fiancé and I got into a huge fight where we almost split to our seperate ways but we still love each other and decided to work it out

However things did start to change he started to be more secretive of his phone and prior to the fight we both had agreed as a couple that both of our phones would have the same passcode our son's birthday

I soon noticed that the passcode was changed and I confronted him about it in hopes that he'd be understanding as I do not hide passcodes from him so I thought he'd understand I'd appreciate the mutual respect but instead it just went into a argument and he continued to change the passcode I guess out of despite but I'm really not sure why he'd need to lock me out of his phone he's told me I'm not doing cheating or hiding anything

I can honestly say that I have gone through his phone before because I couldn't stand the porn usage ..

I haven't asked for the passcode since the fight and have been optimistic that maybe one day he will willingly share it with me

We've been together for about 3 1/2 years now and we have a one year old son

Any insight is appreciated