Adding dot at the beginning of a negative number less than 1,000

[REU8ER]

When working with MoneyMaskedTextController I noticed that when I draw on the screen a text coming from my controller that has a negative initial value less than 1,000 it adds a point between the minus sign and the value.
As a solution for my project I use a replaceFirst to replace the '-.' for '-'

Value before entering controller = -397.5

This is the print of my controller
MoneyMaskedTextController#439e6(TextEditingValue(text: ┤R$ -.397,50├, selection: TextSelection(baseOffset: 11, extentOffset: 11, affinity: TextAffinity.downstream, isDirectional: false), composing: TextRange(start: -1, end: -1)))

This is what renders on screen
R$ -.397,50