I get a Xenforo - Error when I try to log in to the customer section

[MrHamster]

Hey,

I tried to log in to the customer section of Xenforo but I receive this error:

XenForo - Error
This action is available via POST only. Please press the back button and try again.

Can someone help me? The data is sent via POST and repeating it doesn't solve it.

Edit: After going back to the main page and clicking again on customers it shows me the customer section and I'm logged in.