Changing email address

I want to change the email address in my Lebara app as the one registered is no longer in existence. When editing, a verification code is being sent to the nonexistent email address and I can go no further. Several calls to customer service have not resolved the issue. Any ideas what I can do? Thanks

I have the exact same problem,have had 2 contacts with lebara chat this week.They dont seem to understand there is no more contact with the old address.I ended up being told to delink my sim?Wont that cut me off my account?Still I can still get access using my old address,but if i get a problem later on?