My Dualit espresso machine leaks profusely from the top of the brew head?

It leaks before it reaches the coffee filter. I have tried descaling the machine to no avail. I think the plumbing inside has perished or come loose but I can't get into the machine as it needs a special screwdriver like a small allen key with a central hole. Having trouble locating anyone who could repair it locally (Cheshire) as it is too heavy to post.