Security Token Error

[Linue_DarkStar]

So I'm having some trouble with a "Buy Now" button I just created through PayPal Payments Standard. I run forums at http://www.ClanPF.com, and posted the "Buy Now" into a Thread, http://www.clanpf.com/forums/showthread.php?397-Clan-Phoenix-Fire-T-Shirt-White-on-Black, and I went to test it and it will take me to another page with this error:

"Your submission could not be processed because a security token was missing.

If this occurred unexpectedly, please inform the administrator and
describe the action you performed before you received this error."

How do I fix this?!

[Lynne]

This article should help - https://vborg.vbsupport.ru/showthread.php?t=177013

Also note that that form will not work for anybody with moderator powers in that forum (includes all super mods and admins) since you cannot have a <form> within a <form> and the whole thread is in a <form> if you are a moderator.

[ForceHSS]

the pay button seems to work in that post u have above