I cannot upgrade to Premium

[IlkerK]

I made the payment, sent the student verification document and I received a mail saying that my student status is approved. When I click on the link in the mail to complete the process, it says "Not found" on the upcoming website. 

Also, I cannot see my receipt in the receipts section.

Update: I have tried following but still no luck:

- I have only one account. I use the same e-mail adress and did not use Facebook.

- Logged off from all devices and logged in again.

- Tried different browsers.

- Checked with the bank and payment was done, not pending.

- Checked spam box, nothing there.

- Frequently checking account overview but still not Premium.

This is annoying guys please help.