Lost phone, need a new sim

Hi, I recently lost my phone. 

I just need to ask a new sim card from ben, but I cannot find any way to contact them.

I try to log in my account, I know every details of the account but they ask me for a verification code on my phone. Which I can obviously not get since I lost my phone.

I cannot even contact the customer service since they ask me to log in everytime. 

I dont know what to do, all I want is to contact the customer service to ask for a new sim card. 

Thanks for the help, have a good day.