Additional features, settings, or issues not covered by specific Microsoft Teams categories
Hello Rajat ,
My name is Jackson and thank you for your question.
I sincerely apologize for the issue you experience with your Teams , I am a user myself and do not work for Microsoft so I understand how frustrating this is.
The mobile experience is slightly different from the desktop app as you only have the option to request time off in the Shifts app on the desktop. See details in the support link; https://support.microsoft.com/office/02cc8d31-80c6-4dbb-8124-4bd90ef70759
A manager can manage Shifts settings for your teams on Shifts web and desktop. In Shifts, go to Settings in the upper-left corner, If a setting is not available for you to change, that setting is controlled by your IT admin. Contact your IT admin for more info. See details to manage settings in Shifts; https://support.microsoft.com/office/1aef353d-e2df-4661-abdd-4014cb57f17b
Warm regards,
Jackson E