UiPath Exception

[momi_fede (Fahad)]

Hello everyone, in working on the project of the academy I came out of this error someone could tell me what it is due to? I would be very grateful.
@rachrahul2 @tsl

[momi_fede (Fahad)]

to give you a better idea

[rachrahul2 (Rahul Rachamalla)]

Remove the -1 from the argument and try again.