Hi,
Can you send some more information about the server, like for example PHP version and ownCloud version? The form is there to be filled out, that the people here, who would like to help you in their free time, have all the necessary information straight away and are therefore able to help you faster.
Regarding your specific problem, just making sure I understand correctly: are you sending new tokens and they are immediately showing the error message?
Because I think the password reset link tokens expire after 12 hours and this time is hardcoded (I hope I remember that right, otherwise somebody please correct me). So in that case the error message would be expected behavior.
Thanks,
Erik