The first time you install Clerk the default channel is set to #clerk-sms. Any new inbound conversations get posted to that channel. You can easily configure any other channel to be your default one. Once updated all new inbound sms would go to that channel.
Assuming you have invited clerk into your channel (
/invite @clerk) bring out your Clerk menu (
Click on Slack Channel
If you have multiple phone numbers and need to update the association of the channel to a phone number you can do so in the channel settings as well. Once updated the Slack channel would then receive SMS on the associated phone numbers.