Some tax returns take longer to process than others for many reasons, including when a return:

• Includes errors
• Is incomplete
• Is affected by identity theft or fraud
• Includes a claim filed before Feb. 15 for an Earned Income Tax Credit or an Additional Child Tax Credit
• Includes a Form 8379, Injured Spouse Allocation, which could take up to 14 weeks to process
• Needs further review in general

We will contact you by mail when we need more information to process your return.
https://www.irs.gov/refunds/tax-season-refund-frequently-asked-questions