What happens when I don't know ex H's address

[Soopermum1]

Decree Nisi done ages ago. I need to take the finances to court as, after 4 years 😳 he's been so awkward, the finances haven't moved on. He refuses to tell me his address. What do I do when I submit form A? Do I have to get him served? (again)

Does he have a solicitor? You could send it there. Or to his mums. Does he have the kids at all?

No solicitor that I know of. No Mum. Doesn't see one child and never has the other one to stay so I have no idea where he's living and the last time I asked, he refused to tell me. Could send it to his work address I suppose but don't know how often he's at the premises these days

Where does he go when he has his child?

He meets him in shopping malls etc, they meet up about once a week for a few hours

DS said he has moved around a lot and doesn't know where he's currently living