No refund after account closure (bereavement/house sale)

Hi guys,
My late father's house was sold at the end of March. I was last in contact with Electric Ireland by phone on 23rd March to provide final gas and electricity meter readings, which was the day that the keys were handed over to the new owners. As both accounts were in credit, I was informed by the man on the phone that I would be receiving a refund and I was asked which address the refund should be sent to. I provided my own home address, as I did not want the refund to go to my Dad's house, even though I requested the new owners to hand any incoming post for him to the neighbours.

Since then, I have received nothing - no refund and no further contact from Electric Ireland. I have allowed what I thought was ample time for refund processing but am surprised that nearly 12 weeks later, I have had no further contact.

Can you investigate please? I can provide further details via PM.