Hi,
The standard procedure for requesting a new symbol is for customers to fill the online form so that they receive the requested symbol without intermediaries.
When you press submit you should have two options, browser and email, could you try setting the default application of MAILTO to email and try again?
I recommend you check the following page in order to change the default apps of MAILTO
Set Outlook as default MailTo application | Microsoft Community Hub
Best Regards
Pablo