Mortgages and 2 companies disagreeing

I have two mortgage companies on two different propertys. One is mine, another I co-signed on. My bankrupcy was discharged. Both mortgage companies are telling me two different things. One tells me that the minute I made a volunterry payment after discharge, it started the agreement with them again, and they can send me statements to collect mortgage payments. The other mortgage company told me that since the loan was never reconfimred, I can continue to make volunterry mortgage payments but they will never send me a bill, nor reopot to credit. One mortgge company is billing me and reporting payments on my credit reprots. The other mortgage company is not doing that and considering it volunterr payments. What happens in say 10 years. When I keep making the volunteer payments to the one mortgage company can they turn around in 10 or 20 years and take the house since the mortgage was discharged and I never reconfirmed the debt. (they wont let me reconfirm now, said it should have been done earlier, but I can keep making payments).