First suggestion is to be sure you are tracking your refund at IRS link “Where’s My Refund https://www.irs.gov/refunds.
If Where's My Refund shows "Received" (Accepted) then the following link gives information about what to do when your return is accepted but not approved yet and whether you should worry or not.
https://ttlc.intuit.com/questions/2724106-my-return-is-accepted-but-still-not-approved-is-there-a-pr...
