I entered the wrong routing number for my direct deposit. It says I should get it in the mail but it’s been months already and I haven’t gotten any of my tex return money. Please help.

Once the IRS releases the refund (watch here https://www.irs.gov/Refunds ) it is then up to your bank to receive and post the deposit. This can take up to 3 business days to happen as they check to see if it is a legitimate deposit. If the routing & account numbers are correct AND if your name is on the account then the deposit should be acknowledged.  If any of these things are incorrect the bank can refuse the deposit and the IRS will convert the refund to a paper check mailed to the address on the return. This conversion process can take 2 weeks or more to happen.

So ... has the IRS changed the message from DD  to  Paper check in the mail yet ? 

If it does say they mailed the check  AND   it is beyond the date stated that you can ask about it then do so ...

https://ttlc.intuit.com/questions/2557401-how-do-i-replace-a-lost-or-damaged-tax-refund-check