This is the process that works now with IOS 13 and that uses the Files Application
Open the Mail Application

- Select your message
- Touch the attached tune
- If the PocketPipes icon appears, touch it … and that’s all
- If you don’t see the PocketPipes icon, choose register in the Files App
In the Files Application

- Select the Location « On my iPhone » (or iPad)
- Select the PocketPipes folder (the problem is that if it is empty …. it is not visible, so it doesn’t work the first time).
- Select Save on the top right
If you now open PocketPipes the tune bas been imported.
… Not so easy, il was easier with IOS 10 or 11