Please format it properly with the </> button. Should look like this:
mqtt:
fan:
- name: "obk-livingroom-2 Ceiling Fan"
unique_id: "1216C29E_1"
You’ll have to re-paste it as the quotes and indentation are destroyed in the prior version.
Also, that’s not the entire file. Please include everything before the mqtt: as I suspect the error is there.