Can Devaluation Affect A Mortgage Contract? Have A Residential Rental, Mortgage & Cashflowing At Low Interest

I'd like to ask the thread about thoughts on how residential rental assets will do in the near future. If one got into a house at a decent price, (interest rates are relatively cheap with good credit), and is cashflowing the house with responsible renters, (yeah, talent and luck are required here, but that's true of any investment), isn't it true that the contract with the lender remains the same in a currency devaluation situation? In other words, won't I be able to repay the loan with cheaper currency? Doesn't a change in an exisiting contract VOID THE CONTRACT? I don't see anything in my mortgage that says otherwise. Any thoughts?? Thanks in advance!

“I wish it need not have happened in my time," said Frodo.
"So do I," said Gandalf, "and so do all who live to see such times. But that is not for them to decide. All we have to decide is what to do with the time that is given us.”