Ok. Our answers overlapped a bit so I am editing the comments.
If you were in business in 2017 and did not elect to be treated as an S Corp last year and just sent your election with your taxes, it is too late to be treated as an S-Corp for 2017.
In order to be treated as an S corp for 2017, you would have needed to Complete and file Form 2553:
No more than 2 months and 15 days (March 15, 2017) after the beginning of the tax year the election is to take effect, or
At any time during the tax year(2016) preceding the tax year it is to take effect.
Ok. Our answers overlapped a bit so I am editing the comments.
If you were in business in 2017 and did not elect to be treated as an S Corp last year and just sent your election with your taxes, it is too late to be treated as an S-Corp for 2017.
In order to be treated as an S corp for 2017, you would have needed to Complete and file Form 2553:
No more than 2 months and 15 days (March 15, 2017) after the beginning of the tax year the election is to take effect, or
At any time during the tax year(2016) preceding the tax year it is to take effect.
Please see new comments. My screen did not refresh and I did not see your last comment about when you sent in the 2553 before my first answer. See edit. Sorry!
When I spoke with a CPA they said we could still do it for 2017 by putting a specific explanation and it would be used. So thats why it was submitted with the return. Also I am trying to Amend and there is no place to change the type of business.