I'm importing data from a CSV. One column is a phone number and it's mapped to a Zoho phone number field.  The import fails with the error on all rows with phone numbers:

Row 3 Col 10 - The field value '262-1986' needs to start with the + symbol

How do you resolve this?  There is no way to add a + symbol in a spreadsheet cell, as it gets dropped.  

Thanks!