Mom just went into a nursing facility, which took all of her SSA check. How can I stop creditors from calling?

I will assume she is on Medicaid? Next time they call explain she is now on Medicaid and there is no money. Ask what kind of proof do they need. Get their information. If they start harassing tell them you are not, nor any of her family responsible for her debts. You r happy to give them what they need to write off the debt but you want no future calls from them. If they continue to call tell them you will report them to the FTC.