When we update certain parts of the app Google requests a review on their side and an warning appears that the app is unverified.
The review process might take a few days, to continue using the app without issues please follow these steps.
(sometime uninstalling and installing the app is necessary if other warning appears)
Click on the Advanced link to open the settings.
Click on the Go to FileDrop unsafe.
Scroll down and click Accept the new permissions and the FileDrop app will work as before.