fingertrouble | Any freelancers out there than use a managed limited company?

I'm having this argument with one of my agencies about invoices - they keep nagging me about it, I then nag the managed limited company people about it, then it get resolved. It wastes my time, and takes much longer than if they'd emailed my managed limited company direct.

Repeat until fade EVERY FUCKING WEEK.

I finally cracked and said 'Why don't you email this company direct' - I pay them to do the invoices, I know NOTHING about the invoices, and other agencies don't have this issue, or seem to be happy to do this (I've never had to ask them to do this), but this particular agency has problems.

The response from the woman in payroll was 'It's not my responsibility to chase your limited company' - err this is an agency as well as working a lot with in the past I've worked for over a month earning them commission, and am working through one of their clients until September.

And they can't just simply substitute another email address for mine when they chase the invoice?!?

I'm earning money for them and paying this other company to deal with it, so what's the frigging problem? Needless to say the response was rude as hell, so I've sent a shirty email back asking why is it a problem to just email them instead of me when it saves them time and doesn't stress me out?

So any other freelancers out there had issues like this? How was it resolved? Solutions? Ideas? Before I go 'postal on their asses'?