Is this legal?

My husband and I have a joint account. This account is through his work so he is the owner and I’m a joint owner, it’s a credit union so only the owner has access to the account online and through the mobile app. I “borrowed” the password from him and downloaded the app to my phone, yes I know this was wrong but I wanted to know what was in the account as he’s lied about it before. At one point I was going to the atm and just getting a balance but he told me he could see every time I did that. Yesterday I tried using the debit card to get out of a parking lot and it kept giving me an error, I ended up having to use an emergency card my mother gave me as I couldn’t make any calls from the parking garage due to reception. This morning I asked him if he’d disabled my card because I couldn’t get out of the lot and he told me I needed to ask him before using it. He is the only one working as I quit my job to enroll in college (a decision we both agreed on). I’m wondering if this is legal and yes, once this semester ends I will be finding another job and refiguring my school schedule. We are not in the best terms right now, so I do think that’s part of the reason but I’m still wondering if this is legal for him to do.