Length cannot be less than zero "Native Group Aggregation" activity

Hi All, I’m trying to use the Native Group Aggregation activity and the Group By Aggregation activity to sum up all the values of a certain column but I return this error when attempting it with the Native Group Aggregation activity
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Any solutions?
Thanks in advance!

Please refer to the below links:


The values in my excel aren’t strings, they are custom values
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I have tried searching for issues similar to mine but unfortunately they are mostly involving strings