Have you looked at your kernel log? You can post it here for us to look at. Please use the # feature when posting code.

More times then not, if the miner is mining for a short time and stopping it has something to do with your power supply. Please give us some information on your power supply and the circuit.

Both fans will spin on a S9 due to suction. This does not mean they are both working properly. Unplug one fan and then the other and find out which one is not registering. Swap the two fans connectors to find out if it is the board or the fan. It should be showing 2 fans. I have had miners only show one fan and/or 0 hash rate due to insufficient power.