Help adding a negative # error message

[SiaOs82]

I need help with adding a number range for a for statement. If the number is negative -1 then an error message should appear and prompt the user to try to enter another number that is not negative. The user should be able to enter a negative into the program. I can not get it to run once I try to put the range in.

[48T7M4Gy]

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