Microsoft To-Do Sync Issues

I've finally made the switch from Wunderlist to Microsoft To-Do, but it hasn't gone as smoothly as I had wanted.

I am signed into three devices using To-Do: Web client in browser, iPhone and iPad.

I have successfully imported all my tasks from Wunderlist to To-Do, but my reminder notifications aren't showing on my iOS devices. They have successfully synced, but the web client is the only device showing reminder notifications. I have tried closing apps and signing out and back in again, to no avail.

After a little experimenting, the notification will only show on the device where I change the reminder notification time. For example, changing the reminder notification time on the web client results in the notification showing only on that device. The same applies to each iOS device.

Not sure if this is a bug or by design, but I rely on these reminder notifications on different devices to get my things done. I simply can't use it without this ability, which worked perfectly on Wunderlist.

Any suggestions as to where I might be going wrong, or simply some general advice would be greatly appreciated.