I don't think that's wrong. you paid for the price for the post count he had that time. Unless you two have agreement that he had to keep posting, there is nothing wrong
Give a red reputation to him and tell the admin of the forum to ban that user .. Let us know what you did and the result.
practically a joke If he didnt post in the thread that he will continue posting in future at some rate then you cannot do anything as you paid fir his current posts
yea, i sold my sig for life time when i have 600 post.... should i ask the the buy for more money because i have 3000 post now?
Hang on, if the guy didn't specify how many posts he was going to make then he hasn't done anything wrong. If he has stopped posting then maybe he has a duplicate account so tell the mods...... You sold a lifetime link. Unless you die then you have to keep it.
There is nothing you can do. This is why short-term contracts are safe. Work only with professionals you believe are reputable and ethical.
If the seller said he would post x times per month and didn't then I would just tell paypal and get a refund.
But there is a big problem here. Evil signature-buyers can make false refund request (even everything is ok according to their aggreement) from PayPal.