Update wont start because of low memory

Hello, When trying to start OTA-update a message regarding low memory pops up. I have to free up some hundreds of MB to start the update process. My phone is almost clean, few apps installed and just 14 of 64GB used. After uninstalling almost all apps update works, but system itself becomes bigger and bigger, so I fear in near future the device will block itself from being able to update. Happens since last 3 updates.

Device: Gigaset GS290 e_GS290-user 12 SQ3A.220705.004 eng.root.20241008.155328 2.4.1-s-20241008439849-official-GS290

Thank you and best regards Carsten