Yes, I know this, I washed them well and tried to "blow them out" and press them in under vacuum.

Yes, I had that too, it was soooo annoying. I always took everything apart, especially the attachment for the breast and the green round part, took everything apart, put it back together again and then it worked again. Sometimes I even had to do this several times in a row until the vacuum was back. To be honest, I would have preferred to get another one back then, there are so many of these models nowadays.