Sheep people - why would a lamb keep doing this?

[Jdkaksbd]

There are some new sheep and lambs in the field next to my house. They are quite mature lambs and it's nice to see them still with their mums. They all seem happy animals and well kept and are 'hobby sheep' owned by a local lady. They've not been kept in this field before and arrived a couple of weeks ago.
One of the lambs has not stopped bleating. It's constant and has been going on for days, day and night. I can see it, it looks fine and is with it's mum. The owner has been in today and checked them over and all seems fine.
But it keeps baaing! It's starting to drive me a bit potty, in the same way a dripping tap does.
And yes, I like countryside noise, and sheep, and yes I moved to the countryside and accept the associated noises etc, but still it's pretty irritating!
Why is it constantly baa-ing?

Lol. I know nobody can tell me why this specific lamb is baaing.
I thought some sheep owners might be able to give me some insight into sheep behaviour

That's quite unusual. If the owner hadn't been to check I would suggest that it's mother is sibling might be missing but it doesn't sound like that. Do they have much grass? Maybe it's hungry. If the owner feeds them Maybe it's calling out for food.
It sounds pretty annoying. Thankfully ours are generally quiet.

Yes plenty of grass, and spring water

It's not non stop bleating it's a few seconds pause, bleat, pause, bleat and so on

Mum has no more milk.

Have you told the owner? She may like to check it over if she's alerted to it. Sounds hungry or injured

She said in her first post that the owner has been to check it.

Ah right, that sounds a logical possibility. Would that be a problem? Presumably an older lamb is ok eating the grass now? Sorry I'm ignorant on these things

No she didn't, the owner 'checked them over' is what op said. If the animals behaviour is specifically brought to the owners attention she would be able to check that animal over specifically. It is probably hungry from not getting milk and is not yet able to sustain itself on grass. As an animal owner I would be grateful for this specific lamb and its behaviour to be brought to my attention. It's easy to miss one lambs issues out of 20/30/40 plus sheep . . .

Thank you for the information. I will contact the owner to let them know about the frequent bleating in case they need to take another look

My apologies, I completely misunderstood it.