Account Credit refund after service cancellation

I cancelled my business phone/internet service on December 8, 2022, and returned the equipment I was renting before the end of December. On the next billing cycle (January 16, 2023) my account balance showed a credit with the words "final bill", indicating AT&T owed me for the partial month of unused services I had paid in advance. I contacted business customer service to find out when and how this money would be returned to me and was told to wait until February 16, 2023 to see my online account reflect a zero balance, meaning a refund check would have been cut at the time the second full billing cycle came around and all new bills/credits were pushed through the accounting system. I was told the check would cut at the same time the new bills were published, 2 billing cycles after the date of my cancellation (which I was told would be February 16, 2023). I checked my account online today was was disappointed to see that AT&T had still not refunded my money. What is going on? I figured after spending more than 90 minutes waiting on hold and being passed from department to department before being told to simply wait patiently until February 16th that I could rely on that information. Two full billing cycles have occurred since the date of my service cancellation, AT&T has long been in possession of the Gateway device I was renting during my service period, and I have done my due diligence with customer service. Where is my refund?