Renegotiate a lower payment, or lower interest rate that would lower the payment.
Try to defer a couple payments (some lenders allow this)
Find a private lender (someone that has enough money to buy out the mortgage and then you just pay them back under whatever terms they set up with you)
Get a part time job to help make payments
Get someone to rent your basement or a room or suite (this would still be your principal residence, you’ve just got a ‘roommate’ now as well).
Create a budget and really analyze where you money is going and ways to free up cashflow.