Disgusting customer service / no feedback to customers

Since Jet was taken over by RCS my account was handed over even though it had a credit balance and a refund is due to me.

I have contacted the collections team, Jet head office as well as visit the store

I even contacted RCS but no help, I have sent numerous emails and made so many calls but no resolutions

I'm not sure what to do but have no consulted a legal adviser to assist with the situation going forward

Your service is disgusting