Are you running macOS Sierra or lower and have you recently updated your iPhone to iOS 13? From what we’ve seen, this issue has sprouted up recently and is affecting multiple plugin manufactures on Pro Tools and other DAWs as well. Please take a look at the following forums:
Note that the issues in the forums above are from Pro Tools, but it's an Apple issue so it can effect all DAWs on MacOS 10.11 (El Capitan) and 10.12 (Sierra).
From what we've seen this issue effects all Slate Digital and Eiosis branded products (with the exception of FG-X).
Symptoms of other DAWs include the products not scanning into your DAW or constantly being blacklisted.
We can propose two resolutions:
1) Update your operating system to 10.13 or higher.
2) If you have a time machine backup, revert to a backup from before the issue occurred.
Unfortunately the fix for this issue cannot be provided from Slate Digital and would have to come directly from Apple, however the options above provide a workaround.
Here is a statement directly from Avid regarding the issue: