Visit icloud.com from a web browser on a Mac or PC and check if you can see the Just Press Record folder in iCloud Drive. If not, that suggests the iPhone has not synced the contents of iCloud Drive.
Please ensure Just Press Record is setup to use iCloud Drive rather than local storage. Do this by tapping the Settings button in Just Press Record and check the Storage Location setting.
If iCloud Drive is already set as the storage location, plug in your iPhone to a power outlet and restart it. This can sometimes be enough to force iCloud Drive to initiate a new sync. If it does not, use the Settings app on your iPhone and tap on the first item in the list - your name (Apple ID, iCloud, iTunes and App Store). Tap on iCloud then scroll down to find Just Press Record in the list of supported apps. Turn off Just Press Record, then turn it back on again. iCloud Drive should start to sync your recordings.