I think your email address is set incorrectly on your profile
I checked the logs for the service:
May 14, 2020 12:20:18 PM org.jenkinsci.account.Application$User modifyPassword
INFO: User nickbrown reset the password: nickbroon
I then reset the password for myself (and was able to complete the reset):
May 14, 2020 8:50:03 PM org.jenkinsci.account.Application$User modifyPassword
INFO: User timja reset the password:
timja...@gmail.com
There's no error in the logs but I guess it's just a fire and forget email, and it's probably trying to send it to 'nickbroon'
Could be reading it wrong, but it probably needs someone to log in to the LDAP server and update your account
Thanks
Tim