Give back my money which was mistakenly deducted from my savings account(MSA)

Discovery confirmed their mistake by taking money from my MSA, but the action to rectify is long overdue. Each time you phone somebody else wants to know the whole story. I am trying to get somebody senior to explain why it takes so long. Discovery use to have a walk-in facility where you could meet Discovery personnel one on one and they could immediately assist with any queries---nowadays everything by phone and from one person to the next without FEEDBACK to satisfy your needs. All my conversations have been recorded (according to Discovery procedure) so it should be easy to track the history and what was said and confirmed