Phone numbers from a list contains characters that are not standardized. There are unwanted characters like period, dashes or hyphens, parenthesis, braces, brackets, sapces, slashes, etc.
One of the things I do is to reprocess those columns using the Excel formulas below so that what I get is a clean 10-digit phone number.
Just copy and paste it to a blank column on your excel sheet then change the given cell to your actual cell.
=Substitute(substitute(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(H2, “-“, “”), “(“, “”), “)”,””), ” “, “”), “*”, “”), “+”, “”), “=”, “”), “/”, “”)
=Substitute(substitute(Substitute(SUBSTITUTE(SUBSTITUTE(K2,”.”,””), “`”, “”), “_”, “”),”{“,””), “}”, “”)
=RIGHT(I2,10)
=len(H2)