Thanks blip and prl for your advice.
My Fritzbox had "Maintain permanently (recommended for flat rates)" checked as well as "Delay disconnection by provider to the period between".
I have unchecked the "Delay disconnection..." button and will see what happens.
My Fritzbox had "Maintain permanently (recommended for flat rates)" checked as well as "Delay disconnection by provider to the period between".
I have unchecked the "Delay disconnection..." button and will see what happens.