What To Do?

So my husband was recently out of state for work. While he was up there we got in a huge fight because he was smoking cigarettes on the job site and he knows how much I hate smoking! He said he only smoked one which I know was a lie but I just let it go.  He was gone for about a month and just came home last week.  I was going through his phone and found him logged into a gmail account I had never seen before so of course I took a look.  It was a new email only had like 4 emails in it and 3 of them were from him creating an account on badoo (a dating site).  So I went to the sight and logged into his account. Not hard to do since he always uses the same password.  On his account he has one pic of himself uploaded and a pic of his dick.  His profile information stated his location in TN where he was working.  Said he was single listed his hight, age, a smoker, likes to drink, and that he was interested in dating woman 19-34..... I confronted him about it and he claims he has no idea how that account was made and he never made it! He says he think his phone was hacked which is complete BS.  What should I do? Idk how to handle this situation. We have a 6 month old son and I'm overly stressed as it is.  I have already had trust issues with him before and this just topped the cake 😭