How do i get a Line/stripe in a text field for a routine for power consumption? (samsung smartthings app)

[goosetapo (Boaz)]

I have a device thats connected to solar panels, and therefore the watt meter writes minus consumption.
In a smartthings routine, i cannot seem to enter a minus sign…
How do i force a minus sign into it? I tried copy pasting the - but no luck.