Your post is not clear.
If you are saying that auto membership renewal is active, and you are on the Guido membership, then that would explain why €10 is coming out of your card account on a monthly basis.
There is no other way for cash to be pulled from your card by 48.
If you mean that your cash credit balance is depleting gradually (not by €10 at a time since that is impossible) then it may be due to using services that are paid for from your cash credit balance.
But, as I said, this cannot result in cash being pulled from your card - just from your cash credit balance.
Where are you roaming and what membership are you on?
If you are roaming outside of the EU then outgoing/incoming calls and outgoing texts are charged to your cash credit balance.
Hope this helps.