Unable to get assistance with $350 Refund check re-issuance in over a year of calling for assistance

Comcast/Xfinity has not re-issued my refund check (mailed to me previously to the old address) and it had expired by the time I received it. I have called consistently for over a year to simply request a re-issuance. Each time I'm transferred so many times that I end up having to disconnect due to my work schedule. Each call lasts about an hour and I've called countless times with no resolution or assistance. The refund is listed on the CA state controller's office Website for unclaimed property but comcast has not transferred it completely so I then had to call a third party and go through the same situation being transferred until someone was able to determine that I need to contact comcast directly. I am at an utter loss and just want the money that is owed to me.