Hello @AudreySchneider
I am sorry you are having trouble viewing your grades on the Canvas iOS app.
I was unable to replicate the behavior you are describing on my end. Does resetting the cache on the app make any difference?
HERE is a guide on how to access the setting to reset the cache on the app.
You could also check and see if there is an update available for the app in the app store. Sometimes updates will be pushed out to try and fix odd issues like this.
If you are still seeing the behavior after trying those two troubleshooting steps, I would recommend reaching out to Canvas support for further assistance. They might need you to provide them with a screen recording displaying the issue you are seeing and the app version number you are running on the device.
Hopefully this helps!
-Colton