i just want to know what will happen to those account who have negative trust, i know that the best option is to create another account cause he/she cannot use their account anymore by joining signature campaign cause most of the requirements in joining signature campaign is "no neg. trust"
If the intention of that user to join the forum is to communicate in the community, it should be not problem whether they are getting paid or not 
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what will happen to their merits that they earn during the time that their account have not yet tag by DT member?
can they just send it right away to their new account?
Merit will not be affected by -neg trust, so they could either spread the Merit across the forum like it should be or sell it and warrant additional -neg by DT, both to the sender and receiver can they just send it right away to their new account?
Besides, most of users that are getting -neg are either scammers or spammers. It's rare for both of these types to receive merits.