Hi @Charlie Vinall and welcome to Community!
Can you please check if "Story points" is selected here in the Burndown chart?
It happens quite often that "Original time estimate" is selected instead of "Story points", which would be why you don't see story points.
Learn how to use two new reports for next-gen projects in Jira Cloud: Cumulative flow diagram and Sprint burndown chart. Ivan Teong, Product Manager, Jira Software, demos the Cumulative ...
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