Here is a real life case example.
Homeowner had several payments caught up, and sent cashier's check to "trustee" in San Diego. A rescission was recorded. We are only talking about past due of $2,000 plus "fees" for default. Subsequently, no monthly statements ever were sent out and when owner tried to make the next payment, the bank (Chase) refused to take it, claiming the reinstatement was
never made. Owner got attorney to go into the bank and talk to the Vice President. Vice President stated they couldn't see the payment was credited. Attorney continued to try and contact Chase Bank nationwide, to no avail. No one knew anything. Attorney contacted by phone, at least 8 different units, and no one ever knew anything.
4 months later, no one at Chase, or anywhere within Chase nationwide, could shed light on where the payment was, but since the check had not been returned or credited, bank (which issued check) advised to stop payment.
In this case, Chase et al simply refused to take payments and kept owner in perpetual default. There was no other action by servicer or bank except to keep telling owner to "refinance" by modification. Owner didn't want to refinance.
Knowing HBOR was starting in January 2013, the bank and Fannie Mae rigged some deal so that they claimed they had already "sold" the house in December 2012. How convenient. There was no proof they had sold the house on any day in December 2012. Because they didn't do it. Instead, Chase recorded a quit claim deed to Fannie Mae. Then months later, FM claimed they owned property and filed unlawful detainer. In the end, owner left property and filed lawsuit.