@mlk66 .
@macuser_22
options:
1) wait a few weeks and see if the IRS sends more money
2) wait a few months until the IRS call centers are back on line and you can talk to someone
there is one other school of thought on this issue.... which @macuser_22 subscribes to, but I haven't been convinced of yet.
Technically, these stimulus payments are a credit against the 2020 tax returns to be filed next year. Obviously, next year, your son will be 17 and not eligible for the stimulus. It is possible that the IRS is not paying out on those that are 16 in 2019 because they will be 17 and not eligible for the year 2020, which is the year that really counts. That is something that has not been well advertised if that is what the IRS is doing.
