Netflix: I got an indication that I should call the Netflix hotline and subscribe when I wanted to watch an old series?

A few days before we went without problems, a few hours later I've tried again, then it went again without a subscription. What is this subscription hint that sometimes comes. What would they tell you when calling Netflix? I did not call.

No subscription, no Netflix.

But comes only sometimes and I still have the Probemonat

The Probemonat is a subscription. If you have problems with that and you are already being told to call, why not do it and you're done?