Hi @Crocus ,
Assuming you're using currency type columns on your basic form. Once you're creating record from Portal the currency sign is not added by default to the columns instead appear with currency sign but after creation, Portal automatically adds currency sign to currency columns. I think that is the reason why you're getting is doubled after adding your script.
If you have to show it at the time of creation, try to add your script only on create mode when record is not created instead remove it. It should work for you.
Here are two screenshots that I have taken for reference.
1- When adding record to the sub grid using Basic form.

2- It looks like this after I added this record.

Feel free to ask, if you have any questions.
Thanks,
Saud
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