RegularExpression Validation Not Working Properly

I am trying to use the ASP.NET regularexpressionvalidator to apply a password policy that enforces the following policy:

Password should include at least 6 characters, at least one small letter, at least one Capital letter, at least one number, and at least one special character. Here is the expression:

^.(?=.{6,})(?=.d)(?=.[a-z])(?=.[A-Z])(?=.[@#$%^&+=!-_()?]).*$

The strange thing I found is that it works fine except with the following scenario, If I use all the required combination without special character such as Hello123" it finds it as valid password. below is the controls used for testing.