How to accept a shared list?
If someone shares a list with you, you will receive an invitation to accept the shared list.
Open TickTick on your iOS device and slide the screen to the right at the Task tab.
Tap the envelope icon at the top of the screen. Tap "Accept" to accept the invitation or "Decline" to reject the invitation.
After accepting a shared list, it will be automatically added as a list in your TickTick.