Verizon continues to deny credit payment owed to my closed account

[MWP808]

After decades with Verizon and their predecessors, I ported to another carrier in August.  For 3 months after my "final" bill, Verizon continued to bill for several devices which were ported but not removed from the account.  In November, I contacted Customer Services by telephone and was assured by Kyle that a credit would be issued.  This was later reconfirmed by Zel in December, and again on Feb. 7th by Arthur who gave me a ticket number and assured me that an ACH to the bank account I gave him would happen within 5 business days.  No credit yet.  Ticket number is:

PH 9657420.

How should I escalate this situation?

[vzw_customer_support]

Hello MWP808, we're sorry to learn you're having issues with your credit. We will be sending you a private message to further assist. 

~Ivone