Landline service discontinued 5 weeks ago, but no refund received

Early in January I can cancelled my land line service at XXX-XXX-0274.  On 10 January I received my monthly statement showing a credit of $25.72.  The statement tells me that this balance will be refunded.

It's been more than 5 weeks now, and I haven't seen a refund check in the maill or a credit to my visa card statement (the bill was normally paid by a visa account).  I don't think VZ would have accepted my payment 5 weeks late. Where is my refund?

I only have time to work this issue during the evenings and on the weekends.  When I attempt to contact VZ using the phone system, I ultimately get the message that I should call during normal business hours.  I am amazed that VZ does not provide an e-maill address for resolving simple billing issues.

What is it going to take to fix this?