Hello Vanessa,
Thanks for contacting us.
You must upload site icon image in size 30 x 30 resolutions. This image will appear in browser tab on the top of the site.
Please go to Appearance -> Customize -> Site Identity -> Site Icon and upload your site icon here. Then check your site again.
Let me know your issue is resolved or not. If not then contact us again.
Thanks,
Britetechs