I have just sent you an email MNHQ, but posting here in case you get it more quickly.
I somehow got logged out of MN mobile site (usually stay logged in) and couldn't log in again as it didn't recognise my password (I swear it's wasn't a typo or that I have forgotten it!). Came on laptop and could use site as normal as still logged in. I then logged out and again it wouldn't recognise my password to log in again.
I've reset my password using a password reset sent to my email and using my laptop.
I have had to do exactly the same for Ebay so think my phone may be being attacked in some way. Ebay confirmed the password change was made with a different IP to my usual one so I am wondering if you might also be able to trace whether my password has recently been changed (before the one I have just done today at around 14:45) and if so, whether the IP address used to change the password is different to my usual one.