Clearblue advanced - what do the lines mean?

On the blue clearblue digital advanced ovulation tests - what do the lines mean when you take it out? I’ve had 6 days flashy face but the sticks have two lines. Surely one must indicate lh?

Does anyone know?

Also I’ve only tested in the morning. Could I have missed surge?

I’ve not used these for a few months and forgot how much I hate them.

Thanks