Yes, I was a part year resident of both states, and that was clearly indicated. I reviewed all my online entries. The date ranges and income allocation were correctly reported on both states' forms. The only error was taking the credit in Michigan (line 18 on MI 1040). The CA income was subtracted in Subtractions on Schedule 1, Line 13, so no tax was paid. If I had been a Michigan resident with CA income, I would have had to pay MI tax on the income and used the credit because I would have also paid taxes in CA, but then I wouldn't have subtracted the income on Schedule 1. Get it?
I suspect the bug was due to a married filing where one was part year and one wasn't.
I finally got someone on the line (attempt 5) when I said I used the CD/Download. Thank you for that tip. The person I spoke with sent me software to download which wouldn't work on my Chromebook. The online system isn't updated to do 2018 amended returns. Her final solution was to do nothing since it wasn't an error that the state caught. (I think the state calls that fraud.) So I filled out the forms manually. Luckily, I only owe $47 dollars -- $61 with interest and penalty, because Michigan disallowed the original refund.
I'm done with TurboTax.
BTW, I am a finance professional, took an HR tax preparer class 30 years ago, did my own taxes and several others for 25 years, and generally use free tax software in order to e-file. I used paid Turbo Tax this year, because I am not educated on CA taxes having lived there for less than a year. Luckily, I know Michigan tax forms, have filed partial residence 3 other times, and was able to figure this out pretty quickly.
You can tell yourself this is user error, but it wasn't. I hope you look into it.
