To complete the roll a joint/smoke a bong/vape task, you need to do the task with each client, at least, one time. Some of your clients will take their sweet time in showing up at the door, so it may take some time to complete this task. Keep in mind, smoking up with the same client twice, three times, and so on doesn't count. The task must be done with each of your clients, at least once for it to count against the tally. Hang in there, they will all show up eventually!