If I had to guess, it’s your “Type Into ‘Last Name’” activity with the split. You are specifically referencing index (1) but when there is no space in the Name, there is no array element with index (1). So index (1) is outside the bounds of the array.
You can have it check by using an advanced If:
If(Name.ToString.Contains(" “),Name.ToString.Split(” "c)(1),Name.ToString)
This means if there is a space in the value, output the split expression, otherwise just output Name.ToString
This way it only tries the split if there is a space in Name.
No space:
Space:
