Install /e/ on Gigaset GS290 failed "unlock operation is not allowed"

/e/OS Devices Gigaset
3

Did you follow these steps ?

OEM Unlock your device

To flash a custom ROM like LineageOS or /e/OS you need to unlock your device Bootloader. To unlock your Bootloader you as the owner of the device need to approve the unlocking. By enabling the OEM Unlock you are giving your permission for the Bootloader to be unlocked.

  1. Enable developer options and usb debugging following the instructions given here
  2. Allow OEM unlock from developer optionsSettings > System > Developer option > OEM Unlock

From Install /e/ on a Gigaset GS290 - “GS290”