Third party meeting survey auto force link to lowercase

When I use endpoint  /meetings/{meetingId}/survey 

 - Use param  third_party_survey to link with google Forms , but the link i added were auto force to lowercase .

Example :

 added the link 

https://docs.google.com/forms/d/e/1FAIpQLSd5rmLlI2f4CbkEPSLCT/viewform

But when user out room , it show the link 

https://docs.google.com/forms/d/e/1faIpqlsd5rmllI2f4cbkepslct/viewform.

Any ideas what's going on?

Thanks