You can report the excess contribution to your 401K on line 7 of your 2017 Tax Return without a Form 1099-R by following these steps: 

• Click on the "Federal Taxes" Tab
• Click on the "Wages & Income" Tab
• Click on "I'll choose what I work on"
• Scroll down to "Less Common Income"
• Select "Miscellaneous Income" and click Start or Update
• Select "Other income not already reported on a Form W-2 or Form 1099" and click on Start
  
• Answer the Question "Did you receive any other wages?  Yes
  
• Click through the questions until you get to "Any Other Earned Income"
• Answer Yes to "Did you earn any other wages?
• Indicate "Other" as Source of Other Earned Income and click Continue
• For the description enter "2017 Excess 401K Deferrals" and click on Done