BOUGHT BURGERS FOR R59.90 BUT CHARGED R459.90

I bought 2 x burgers for R59.90 on Wednesday morning the 24th July. I swiped my bank card for payment. Card no ***0.... Ref ***. My account was debited with R400 on the 26th ref *** at 21h45 whilst the shop was closed using my card no ***0.. The correct debit of R59.90 went through on the 27th July. I went to the shop to query the R400 debit and the manager refused to refund me to date. Please help as I need my R400 back.