Frustrating out of box set up

I’ve set up accounts for all family members and setup Homebase 2 and doorbell. It now works for 3 of the family but can’t get the fourth to login. Created new accounts, deleted eufy security app and reinstalled.
Deleted invite and sent new but app simply will not allow login - failed request.
For the cost of this item the setup should be seamless.
FAQs are useless, forums like this full of dissatisfied customers on setup but no solutions that can be carried out by the end user.
I assume the system has to be reset with EUFY/Anker or somewhere else - who knows??
All I want to do is have access to the doorbell rather than wasting my time trying to get someone from the company to do something to help!! Rant over…for now!