Unable to refresh QuickSight Dataset

Hello,

I inherited a QuickSight Dashboard, Analysis and Dataset from a colleague who is no longer with the organization. The dataset is based on a custom SQL pointing to a PostgreSQL database. I was granted ownership of the dataset. However, I am unable to refresh it because I receive the following error:

"You can't execute the custom SQL query because you don't have sufficient permissions to connect to the underlying data source."

I am perplexed, I do have access to the data source and it is a shared data source. What do I need to do to get the dataset to refresh?

Thank you.