(please share the FULL error message you see, if applicable)
Other Information
I’m using WordPress with the Paid Memberships Pro plugin. I have an issue where the login fails on the first attempt, but succeeds on the second attempt:
First Login Attempt: User submits correct credentials on the custom form. The system redirects to the standard, wp-login.php form.
Second Login Attempt: If the user enters the exact same credentials on the wp-login.php form, the login is successful, and the user is correctly redirected.
It sounds to me like the problem isn’t that it only works on the second attempt, it’s that logging in only works on the wp-login.php page, not the custom form. You’re not filling in the same form twice, you’re using two different ones.
So it seems to me that your custom login form just doesn’t work. Unfortunately, I don’t know enough about WordPress, let alone this specific plugin you’re using, to tell what even provides that custom login form, and why it might not work.
I don’t see anything that seems like a hosting issue to me. And if it is, I would need to know more about how exactly our hosting would be preventing that form from working, or what we would need to change.
In any case, you need someone who knows WordPress (and maybe that plugin) very well to say something useful.
You can wait for more replies here, but please understand that this is a hosting forum, not a WordPress forum. So you may find better answers elsewhere.