How to save links to firebase that are provided by my user

I have one text box to input url which take url from user but it is saying (.,-@&) symbols cant be used that why i cant receive link on my firebase. any suggestions ?

change the @ with anythin a x or so.

I am going to add to this. Whenever I have an @#$% . I need to remove, but then replace later, I have a standard formula.

ReplaceAT
ReplaceNUM
ReplaceDOLL
ReplacePER

Point being I created something, case sensitive that makes it very easy for me to do a replace both ways if needed.