Your phone must be able to scan a chip. Make sure that your phone is updated. Go to Settings on your phone to see the version of the operation system.
Read more about the technical requirements on MitID.dk/technical-requirements
This guide is for Danish, Greenlandic or Faroese passports. Check that the expiration date of your passport has not passed.
Your passport must have this symbol on the front. This means that there is a hidden chip in your passport and that the chip can be read by the MitID app - confirming who you are.