Issue about send later(add on)

Thunderbird add-on About send later, if I set the sending date and time and register it, it will be displayed in the draft, but when the date and time come, it will jump to the sentbox of the local folder, and it will not actually be sent.
The version of send later is 9.2.7.
Thunderbird is also the latest 102.6.1 (32bit).
Anyone know the cause?