Assign : Input string was not in a correct format.Assign : Input string was not in a correct format

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3

thanks,

I’m trying to do the same work as in:

How do I group by one column in the datatable and take the sum?

The values to be summed are in general:
-732,70
-51,30
-23 040,00
131 333,86
-107 510,00
0,14
-2 514,67
2 514,67
-2 710,00
0,49
35 449,51
-32 740,00
-3 899,00
3 899,19
-0,19
9 049,88
-4 893,74
-4 156,00
-0,14
-990 444,20
-13 539,69