The only person that can permanently remove a signature is the administrator of the site. Moderators can remove signatures from individual posts only.
How long was your signature? If over 10 lines then that might have been the cause.
Did you have a link in your signature? Some links are not allowed depending on where they go to.
Did you have anything controversial? Sometimes sigs are removed if people include things of a political or controversial nature.
Let me know.
Moderator Crohn's Disease Forum
CD, Ankylosing Spondylitis, lupus, small fiber peripheral neuropathy, avascular necrosis, peripheral artery disease, degenerative disc disease, and a host of other medical problems.