You shouldn't be adding additional accounts to a workflow after they are initialized as they won't show up for the user until the next year. To do this you need to follow the steps below.
1. Go to General Ledger -> Budget Workflows -> Budget Dashboard.
2. Select the budget you need to change.
3. Click delete
4. Go to Administration -> Budget Workflows
5. Click initialize budgets
6. Select the budget description
7. Select the proper 0 period (ie 00/20)
8. Click initialize
Should you need to add a single account to a budget after they have started entering numbers, this can be accomplished on the dashboard
1. Go to General Ledger -> Budget Workflows -> Budget Dashboard.
2. Select the budget you need to change.
3. Click Show Details
4. Select the account from the drop down