Why do I get a 'food burn' alert every time I use my pressure cooker?
A quick google search illustrates that this appears to be a common concern for instant pot users. Have you checked the sealing ring, steam release, and float valve to ensure that they are clean and working properly?  You may just need some cleaning and preventive maintenance.  You don't mention the brand, but you can begin with your user manual.  Here is some information specifically about the Instant Pot brand cooker.