[AnthonyTimmers]

Use a timer.

Код:

SetTimer("UnVIP", 60000, false, "i", targetid); // 60.000 milliseconds = 1 minute, change it to whatever you want.

forward UnVIP(playerid);
public UnVIP(playerid)
{
    // Make player not a VIP anymore
}

If you are saving the VIP level somewhere, for example on log-out, make sure that it doesn't save a temporary VIP level.

+Rep if I helped you