Businesses cannot force people to comply with any rule they decide to make up. There is no legal basis for the bank to mandate masks. What if a bank made a rule that all women needed to wear a hijab? She didn't agree with their policy and was in the process of removing her money. The bank was using the police to prevent her from recovering her own property. You cannot trespass someone who is in the process of retrieving their own property. This will be an interesting case. Ironically, it is illegal to wear a mask in a Texas bank.