A tank cannot be reprogrammed between regular resins and the more chemically aggressive resins
I’m not sure which “family” of resins Model is considered to be part of (Dental?) but I’m guessing it’s considered more chemically aggressive than standard resins so you aren’t allowed to switch.
There’s some discussion about that in the two threads I linked and it sounds like Formlabs might be considering relaxing the restriction. I encourage you to chime in or contact Support and let them know if the status quo created a problem for you.
In the meantime I think you’ll need to buy a different tank.