was your return e-filed and accepted or did you mail it? have you used the IRS refund website to check on its status? did you move since filing or if direct deposit was requested, did you close the a/c?
while the IRS is far behind in refunds, 5 months seems to be excessive. unfortunately, trying to get through on the phone to the IRS at the present time is extremely difficult.
First choose your language.
When asked for SSN do nothing it will ask twice
it might be possible to set up an appointment with your closest IRS office