There are some reasons that may cause a delay , If you claimed a EITC , then the delay is due to The Path Act.  See below for details:  https://ttlc.intuit.com/replies/5556415

You can contact IRS at 1-800-829-1040.  Customer service representatives are available Monday through Friday, 7 a.m. to 7 p.m. local time, unless otherwise noted. Residents of Alaska and Hawaii should follow Pacific time. Puerto Rico phone lines are open 8 a.m. to 8 p.m. local time. Other reasons for delays are see below:  https://ttlc.intuit.com/replies/3302330