assuming the voucher paiment went through correctly and is sitting in available funds and 2) teh available funds is greater than plan cost.
1) try rebooting your phone
Paid $30. On account but phone not activated
Is your plan $30? Try adding additional payment of a few dollars. Does plan status say active? If making another payment and lost-stolen suggested before doesn't work, send private messaging to Moderator_Team.
First of all, You select a plan first. Second you use your voucher after. If your phone does not work. Try to turn it off and on. And then go to 611 on your phone and check if your voucher amount is already on self-serve. Try to log in in self-serve on public mobile and check you amount you have entered. It suppost to work that way unless is your sim card is not working properly. Also remember that your phone number must be on public mobile self-serve website.
I hope this will help.