A channel cannot be deleted if it has active transactions or customers linked to it.
Attempting to delete such a channel returns 409 CHANNEL_IN_USE.If you need to stop using a channel:
Stop routing new requests to the channel (channelId in payment requests).
Wait for all active transactions to reach terminal states.
Delete the channel once no active references remain.
Alternatively, reassign the default channel to another before deleting, if applicable.