diff --git a/Core/Src/yunhorn_sts_process.c b/Core/Src/yunhorn_sts_process.c
index dce2733..31d5352 100644
--- a/Core/Src/yunhorn_sts_process.c
+++ b/Core/Src/yunhorn_sts_process.c
@@ -157,7 +157,7 @@ void STS_YunhornSTSEventRFAC_Process(void)
 		if ((rfac_timer >= STS_BURN_IN_RFAC) && (rfac_timer < (STS_BURN_IN_RFAC +3)))
 		{
 			APP_LOG(TS_OFF, VLEVEL_M, "\r\n -------------------RFAC Process\r\n");
-			STS_SENSOR_Upload_Message(LORAWAN_USER_APP_CTRL_REPLY_PORT, 4, "RFAC");
+			STS_SENSOR_Upload_Message(LORAWAN_USER_APP_CTRL_REPLY_PORT, 4, (uint8_t*)"RFAC");
 		}
 		if ((rfac_timer > (STS_BURN_IN_RFAC + 2)))
 		{