If you have sent yourself a password reset and it doesn't work this may be due to a number of reasons:
Reset tokens last for 6 hours. If this time has expired a new one will need to be requested in order for it to work
You may have inadvertently sent two reset tokens to yourself (this can be done by double-clicking on a slow page). The second request will over-ride the first but they may not be received in this order so the token may not be valid. To resolve, please send another password reset to yourself and ensure only one click is made.