Dear Guo Yunfeng,
thank you for contacting us.
Currently, this error is usually raised when a pointerUp event is missing. For each stroke that is added, you must ensure it starts with a penDown event and end with a penUp event: https://developer.myscript.com/docs/interactive-ink/1.2/android/fundamentals/editing/#incremental-input
Best regards,
Olivier
thank you very much,you are a hero.
guo yunfeng
When we recognize, we run into a problem "pointer with same pointerId has a trace already pending".
this problem happened once in a while.