I would go to the dealer and ask for a meeting with their Ford Company representative.I have a 2017 Escape, I received a letter late January 2020
I received a letter regarding a 'customer satisfaction program 19B37' I took it to Ford and it was too late to fix this issue. Coolant leaked into the cylinders and the engine is damaged. Unfortunately my warranty expired. I missed it by 3,700 miles! Now I need to pay out of pocket for a brand new engine. I do not have $7,000 for a new engine, I'm still paying for the car, I have 2 jobs and I can't drive my car.
I suggest you go get that taken care of as soon as possible before it's too late.
The fact that that you are only 3700 miles past the warranty and the issue has been going on for a while to cause the engine damage is essentially proof that the problem started during the warranty period.
Be firm and be nice, but don't be afraid to stand up to them.
Given your situation, I would consider contacting one of the local news outlets "consumer support" reporters.
Show them this thread and how far back the issue goes.
Best of luck!