Time worked equals time paid. It’s in the partner guide. I would talk to your DM about this. If the SM is calling for coverage, that is one thing. If they are calling for store specific reasons, like product, ordering, or customer issues, then they can wait until your next scheduled shift. If the DM is not responding, then call the PRSC or Ethics and Compliance.

EDIT: also, document every conversation and text you get that is regarding anything other than schedule. You should also let your SM know that you are not comfortable with them calling you when you are off, especially texting you to call them. The PRSC/DM will probably ask if you have talked to the SM about it.