The start switch on my mother's 2012 Lincoln MKX pushed back into the dash. I think she must have pushed it too hard ::) only takes a light touch. I couldn't get to it from behind the dash with my meat hooks. I did manage to loop some fishing line around it to pull it up flush. It appears whatever clip locks it in place may be broken. My favorite body shop doesn't work in that arena & suggested the ford dealer. I haven't youtubed it yet, always sumthin',can't just go fishing, naw !!!
Use a small screw driver to pry out the round plastic cover around start switch ,that cover have some plastic legs to hold start switch in place . These legs may be broke off then you have to glue them back
In case you can't fix it you can order after market one
https://www.ebay.com/itm/387282243646?