I changed my state of legal residence from PR to OK effective 22NOV2017. OK hasn’t taken any state taxes. Is this an issue?

OK requires you to fill a return for anything over $1,000 worth of OK source income regardless of residency status. I'm assuming that you changed your HOR to OK on 22NOV2017. Which means that your December pay would be considered OK based income. You'll need to file both PR and OK returns.

I've owned rental property in OK for the last 10 years and forced to file an OK return every year. However, under the SCRA Oklahoma cannot actually tax my income there. I include the rental income into my HOR tax return. Which fortunate for me allows me to claim exempt while I maintain an active duty status. :) If you want more in-depth knowledge you can find it at OK Tax Commissions site https://www.ok.gov/tax/.

SSG (Join to see) Have you checked your LES to ensure the "change" was effected and what date did it start- you may have to go back a few LES's to see.