I need a pay out from my father's ABSA TRUST LTD

My Dad died 10 year's ago so and he left me money in the ABSA TRUST LTD and I was suppose to receive that money when I reach 18 which is after grade 12 and now I have passed my grade 12 and tried reaching out to them after I was accepted in University so that I can get the money to pay for my year course but they told me the money is finished and I don't understand how and I need the money to pay for my year course or I won't be able to further my studies next year