An RTC timer error occurs.

The following figure was taken with "#define RTC_USE_32K_RC_ENABLE 1" at rtc.c of "telink_mesh_sdk".

The timer works well, and at some point the time jumps.

1) Sleep mode is not used. It's always in normal mode.

2) When logging the timer, there was no action, only logging to see if the timer worked properly.

In this situation, is there a way to calibrate the timer? Or should I not use 23k RC?