Unable to Untick Read Only child table field

ERPNext
,
#1

I have my Quotation Form, and i add a item to Quotation Item, and im not able to change the field “Costo Unitario” (price_list_rate).
I Have some products without price, so i have to add that product and set a price in that “costo unitario” field. But im not able to change the value, the field is disabled.

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If I open the Edit Grid, Im able to edit the field, but not in the small table view.
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So… i went to my Quotation Item DocType, and i wanted to UNTICK the “READ ONLY” field.
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and i couldnt, a error message comes…
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Im Logged in as Administrator.
Thanks!

#2

hello, you can try Customize Form

#3

Yes, I already customize my doctype and tried to uncheck the “read only” field. but i couldnt, as you can see in the picture i uploaded.
my version is 14, i had the version13 before and i had no problem with that version, the problem cames when i update to 14