No food, no gas, no help from Standard Bank

I am currently overseas and have not been able to use my Standard Bank Mastercard since Sunday the 11th of December at any pay point. The card is active, funds plenty and EAP limit not exceeded. Also activated for overseas use. I have sent urgent emails and tried live chat on the app, but with no success. I am unable to buy food, gas or fuel. I cannot phone the helpline from the UK due to the exorbitant cost. Desperate situation with no aid from the bank!