***The Restore Purchases Feature does NOT restore the purchase of the old Notion for iOS app. It ONLY restores in-app purchases made within that old app. ***
To restore previously purchased sounds, go back to the Application Menu (the 3 dots at the top right-hand corner of the screen), then choose "Sound Installation." Scroll past the 'Core Soundsets' to the 'Expansion Soundsets'. Items you have purchased will show as 'Install' rather than 'Get'. If you have not purchased Expansions Sounds in the past, you will not have them available in this window - the 'Get' button will take you to the Manage Features dialog.
Note that the soundsets have been reorganized in this new version - if you had individual sounds purchased in the past, these will still be available to you but as part of their parent soundset, which will now be unlocked and ready for download.
For the Handwriting Tool, it can also be restored if you purchased it in the past. If you are a using an Apple Pencil, you should be able to start writing directly into your score without switching modes. If you are using your finger or a generic stylus however, then first, start a new score or open a score. Next, tap the Application Icon of the 3 dots at the top, right-hand corner of the screen. From there, go to "Options" and select "Extended Palette." You should now see an icon of the Handwriting Tool in the palette. It is an icon of a pen at the top left of the screen. Once you choose that icon, you can then write directly into the score.
*** Restoring purchases will only work if you have previously purchased expansion sounds or the handwriting tool in the Notion for iOS app. If you have not made such purchases, then there will be nothing to restore. This function will only restore purchases made on the same platform. You cannot use this function on one platform to restore purchases made on another platform. It will not work. ***
If you still cannot access these functions, check you are signed into the device with the same Apple ID with which you made the purchases through. This is the number 1 reason why Restore Purchases does not work! To check your previous purchases exist for an Apple ID, follow the instructions here: https://support.apple.com/en-gb/HT204088#device
You can also try signing out of your device, then signing back in. Go to Device Settings>Your name>Scroll down>Sign out. Once you have signed back in, go to Notion Mobile>Manage Features>Restore Purchases.