Mossy, bald patches in lawn

[KubaLeebre]

We bought our property in February and have noticed that there are large patches where grass doesn't grown in the lawn. Instead, it seems to be covered in a fine moss, or bald. Any ideas why this might be?

In another part DH has dug over and reseeded, but there is a bald patch where the seeds haven't grown. Any ideas?!

Previous owners had two dogs - could it be related?

Rake, water, seed, cover with chicken wire to keep birds off
and wait.

That could be caused by the patches where female dogs have peed. It happened in our garden when our dog was a pup - we've since trained her to pee only in one spot.
If it is due to dog wee then hopefully after a bit of time it should recover. Time will tell.