Appalling Service - ready to go social media with FNB

We own a lodge in Herm****. One of our guests left a gadget behind and asked the Farm Manager to post it to her while she is still in Cape Town. She put R350 in her account to cover the courier costs and petrol. She paid the money from an overseas account. FNB is REFUSING to give her the money, cross-questioning her and making her feel like a ********. This is HER money, not FNB's. She has all the proof FNB need, FNB hasn't even bothered to call me. Please call me so we can arrange to get her paid. It's her money, not yours to control over as you like. I'm going to put this all over social media if I don't hear from FNB and get this sorted out and her money paid to her asap! I can't even phone FNB - I've been on the phone for over 15 mins waiting for a manager.