The requirements to appeal a voucher ban are not affected by how long it has been since the ban was placed. A voucher ban is still a voucher ban even if it has been 5 years.
Ban evasion is the most common cause of a voucher ban. Each evasion attempt resets the minimum waiting time so that you may not appeal your ban for at least 6 months from your last attempt at ban evasion.
An exception will be made to the waiting period and voucher requirement only if you successfully argue that the ban was inappropriately placed.