Riehechop19 When you create a Netflix account, you're asked to set an e-mail adress and a password, for the login. if you forget your passoword you will be asked to enter an e-mail adress, see image below.

The problem is, you will only get this e-mail to the adress you entered, if it is the same adress you used, when you made the setup to your account! If it is not the same, you won't get anything, even if it is written "E-mail sent.....". This makes completely sense, because other you could get the possible to set a new password for other account. So the adress you should enter must be the adress you used when you created your account. If you no have have the same adress or the adress is the for both cases you need to contact Netflix directly (see link), as it is not a Swisscom related problem.
In both cases, could it be that you created the membership with an e-mail adress, that is nor more valid?
Netflix Help Center