UART to MQTT communication using buffer

Hi all ,

I am using Quectel EC200C-EU device, i am taking reading from AC meter using main com port of uart on this board, i am successfully able to read and write hex value from ac meter ,i am using uart_demo.c for and futher and try to send data to mqtt server using mqtt_demo.c for this.i am trying to copy hex values from one buffer to another buffer but i am not getting that hex values in mqtt file ,so i have tried with hardcoded method using global buffer but still didnt get value

[ql_MQTT][PrintHex_1, 99] 00

please help me in this.