2017? And you are just now asking about it? If you filed IN 2017--are you asking about your 2016 tax return---or do you mean the 2017 return you would have filed in 2018?
At this point--you have to contact the IRS to find out.
To call the IRS:IRS: 800-829-1040 hours 7 AM - 7 PM local time Mon-Fri
Listen to each menu before making the selection.
First choose your language. Press 1 for English.
Then do NOT choose the first choice re: "Refund", or it will send you to an automated phone line.
Instead, press 2 for "personal income tax".
Then press 1 for "form, tax history, or payment".
Then press 3 "for all other questions."
Then press 2 "for all other questions." It should then transfer you to an agent.
Another thing for you to try--see if the IRS has a transcript for a tax return you filed. It is possible you did not really file it--it may have been rejected and you did not notice. (Although most people would notice not receiving over $1800.) If you filed they will have a transcript.
You can get a free transcript from the IRS: