The latest release of OnStepX is version 10.20a:
github.com/hjd1964/OnStepX/releases

If using later than that you are running something significantly less proven.

Also, make sure DEBUG mode (Extended.config.h) is disabled if using a serial/USB for comms.
Also, make sure you flash according to the OnStep Group Wiki instructions (else the ESP32S might be crashing for all I know.)

If none of that does it post some INDI logs to the OnStep Group.

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