Does anyone know why I can’t categories my transactions via my phone and why I keep getting error 1186 reason iPhone?

Welcome to the Community, @theheadstocksatbrinsley. While we can't provide a definite answer for why you're encountering error 1186 when categorising your transactions on your mobile device, we recommend refreshing your app's data, as this often resolves most errors.

Here's how to do it:
 

1. Go to your phone's settings.
2. Select General, then choose iPhone Storage.
3. Tap QuickBooks Online from the application list.
4. Select Offload App to free up the storage without deleting the documents and data for the app.

If the error persists after the refresh, please contact our Live Support team so they can look into this matter using their tools. Just be sure to reach out during their support hours.

Should you have any other concerns or questions, feel free to let us know in the thread.