Hello @ThabisoMokoallo-9519 ,
It cannot be reenabled as far as I know if you cancelled it . If it was obtained through any online promotional scheme like Microsoft Build etc. it does not have a way . If it was provided to you by some partner or a Microsoft contact and its credit validity still stands then you can try creating a support ticket at https://azure.microsoft.com/en-us/support/create-ticket/as suggested by DSpatrick above and the subscription team will help you to figure out if anything can be done.
Hope the information is useful . If you have any further queries , please let us know and in case the information in this post or the other post is helpful , please do accept one of them as answer which can help other members of the community with similar queries.
Thank you.