Contacting NOS by email

Hello,

can anybody help me? I have to contact NOS and send them an email with informations that I payed the last invoice, but I can’t find an email adress where I can sent it.

When I try to phone with them, noone can speak English and they hang up or pass me through to another employee who also doesn’t speak English or the contact interrupts.

Also in my NOS account I don’t have the possibility to sent something.

Thank you in advance

Christina