A. To manage the automatic addition of the +91 prefix, you can manually remove it when entering your phone number if the app allows you to edit the number after it is generated. If the app does not allow this, consider using a different phone number that does not require the prefix for your intended use.

B. If you need to enter a number without the prefix for a specific purpose, you can try entering the number without the prefix in the app and see if it accepts it. If it does not, you may need to use a workaround like the virtual phone number service mentioned earlier.