Siva is right that's a service charge clause - muppets.
Point it out to the Judge that they can't even read and quote the right bit of lease, so how can they property instruct solicitors.
And if course quote the right clause of the lease and point to the fact that they cant enforce recovery without the statutory information. Point them to the Section 47/48 cases and the Summary of rights cases.
And then ask for the section 20c LTA 1985 order if they do intend to add costs to the service charge, or that the LVT are directed by the court to determinate it and return it to the court to rule.
When the beak struggles you say all I wanted to was to pay and fair and reasonable service charge if they carried out the repairs that their client is reasonable for, or approached it with a modicum of professionalism and common sense, not litigation. You have subsequently learnt that while it is not the law but understood that an agent needs funds to do so, they could had should have discussed that they could repair, but need £x and plan to do y to solve it all. Mediation would have achieved that.
Based on the information posted, I offer my thoughts.Any action you then take is your liability. While commending individual effort, there is no substitute for a thorough review of documents and facts by paid for professional advisers