Gains. Purchased a House with Sons funds. House was in my name only. He paid the Mortage.

Please clarify your question with additional information.  For example, you indicated that you received a 1099, who or what entity sent you this 1099?  You also indicated that the 1099 references $150,000 for which you never received.  Where on the 1099 is this $150,000, namely in what box number was the amount entered?  

You stated that in October 2021 your son "purchased a mortgage for $203,000," and that your house was paid-off.  It appears as if your son received $203,000 and then used part of those funds to satisfy your mortgage.  Is that what happened?  If those funds were in fact used to satisfy your mortgage debt obligation, then you would need to include those funds as income on your tax return, and you would likely have to pay tax on those funds.  It does not appear as if your son actually gave you $150,000; however, the fact that you never received the actual cash or a check does not matter for tax purposes.  As long as the funds were used for your benefit, such as paying-off your mortgage debt, you are still considered to have received those funds.