Fitbit App sideload fails with Internal error
Solution 1:
See: https://community.fitbit.com/t5/SDK-Development/Simulator-SSL-Problem/m-p/5003032/highlight/true#M16148
It is a simulation problem, I believe. You have to delete the cacert.pem in the simulator, and replace with a new and updated version of cacert.pem in the simulator folder for Versa 3 . Click on this forum discussion to find the cacert.pem download and instructions. The simulator has been broken for a while as announced in November on the Fitbit Development Twitter.