I haven't received my titanium card.,I wonder if it is lost?

None of us here are Apple employees, just users like yourself volunteering to try and help. These forums are not Apple Support and Apple doesn’t respond here most of the time.

That being said, the titanium card does not automatically ship upon acceptance of your application. You must specifically order it. Otherwise it will not be sent.

Request and activate a titanium Apple Card - Apple Support

If our attempts at helping are not satisfactory then contact Apple Support

Contact Apple for support and service - Apple Support

Did you receive the email with the tracking information? This is sent when the card actually ships. The email would have been sent to your email address associated with your Apple ID/iCloud account.

I still have not received my titanium card