Hi I want to specifically connect a Deco M5 to another assigned deco M5. It now does this automatically, but I want to set it manually because it always chooses the wrong one. I have 5 of these Deco M5 devices and want to set them all up manually

When I go to devices in the Deco 3.0 IOS app, then select the device. Then click on the desired connection and then switch the slider, it immediately says 'saving the settings failed. Try again later'

How can this be solved? I really feel the urge to return the products :(

Tried:
- Updating to Deco 3.0 IOS app
- Firmware update on all deco
- Rebooted devices

- Removed all devices and added them again

- Different phone
- Different admin account on Deco app