AT+SMSTATUS and SMCONF throws ERROR- SIM7000C MQTT

[jatayu86]

I am currently using SIM7000C with version 1351B037000C . I somehow cannot make the MQTT work, as in AT+SMSTATUS or AT+SMCONF throws ERROR. HTTP works fine with success responses.I am not quite sure if mqtt is supported in this version. I am trying to upgrade to a later version like B05 ,but cannot find the fw files anywhere.Does anyone have this or a later version with you,or where can I find it for download.