@gop1250 --
Your employer should not be withholding CT taxes. See Example 6 on page 8 of the Connecticut Employers Tax Guide:
https://portal.ct.gov/-/media/DRS/Publications/pubsip/2021/IP-2021-1.pdf
Unfortunately, as @Hal_Al said, in order for you to obtain a refund of the mistakenly withheld taxes, you'll have to file a non-resident CT tax return. On that return you should allocate zero income to CT, but show the CT withholding. That should result in a full refund.
I doubt that you will become a "test case", because CT tax law is very clear that non-residents of CT who never work inside CT are not liable for CT income tax on their work earnings.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
