I have found some similar threads, but the solutions did not seem to work, here are the specs:
iPhone SE 1st Gen - 14.2
DJI Mimo - Fresh install
Osmo Mobile 3 - Firmware Unknown

So my phone sees the Osmo and connects, but when in the Mimo app it fails to connect and states: Unable to activate device. Contact DJO Support for assistance.

I can use the basic functions, like recording and taking pictures through the standard camera app, but that is it. Any ideas please?

Hello there Ellruss. I am sorry for the trouble this has caused and thank you for reaching out. Can you please try using a different mobile device for us to be able to isolate the said issue? Please keep us posted for further assistance. Thank you.

Hi, I just bought a OSMO Mobile 3. OM3-40SQXB-2