Sergio,
Try pasting this into a simple formula text field. It converts the string to all numbers and then inserts the delimiters back into the string.
Change [Raw input] to your field name.
var text MyString = [Raw input];
var text PartOne = Part($MyString,1, "./-");
var text PartTwo = Part($MyString,2, "./-");
var text PartThree = Part($MyString,3, "./-");
var text PartFour = Part($MyString,4, "./-");
var text PartFive = Part($MyString,5, "./-");
var text AllNumbers = List("",$PartOne,$PartTwo,$PartThree,$PartFour,$PartFive);
Left($AllNumbers,3)
& "."
& Mid($AllNumbers,4,3)
& "."
& Mid($AllNumbers,7,3)
& "/"
& Mid($AllNumbers,10,4)
& "-"
& Mid($AllNumbers,14,2)
