Hi @Sushrut Paranjape ,
You can try to deploy spfx with webApiPermissionRequests again first. This error is usually found when the App catalog is newly created and app is added immediately after App Catalog creation. Just remove the app and wait for about 30 minutes and deploy again. If this doesn't work. You can try to removed "isDomainIsolated": true,
from the package-solution.json file. This also might cause the error. If all above doesn't work, you might need to grant tenant with Sharepoint Admin permission to fix this.
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