sd_ble_gattc_characteristics_discover(conn_handle, handle_range);

[0_velan_1]

sd_ble_gattc_characteristics_discover(conn_handle, handle_range);
HI, here conn_handle what parameter need to pass and m_clientService declaration where you did?

[Kenneth]

Seems like a duplicate of:

https://devzone.nordicsemi.com/f/nordic-q-a/75160/hi-here-sd_ble_gattc_characteristics_discover-conn_range-conn_range-what-parameter-need-to-give-if-suppose-through-uart-i-am-sending-data-like-at-command-format-means-at-ubtgdcs