Tenant locks me out of common areas

I’m a new landlord with an inherited tenant in the upper unit of a duplex. I’m only a week in and twice have found myself locked out of the common entrances by a locked screen door (with an unkeyed latch lock). After calling the tenant they have let me in, and both times have said “we lock it when we come in at night”. Keep in mind this is a shared entrance for both units.

I asked them not to lock it as I have contractors coming and need to work on the lower unit. It happened again tonight and they seemed frustrated at me (swearing even) as it was a bother to let me in to my own property. And I should have called them.

They have been uncooperative about giving me a key to their unit - I had to almost corner them. Clearly they feel special need to control their doors!

My calmer judgement tells me to install a better inner door lock so they feel comfortable leaving the screen door open, and explaining that common areas must be accessible to all tenants and property management. However my evil side wants to disable the locks and charge them a lockout fee.

Rant over. What would you do?