leaking brake valve

Waco Demon said
Has any one had problems with new brake valves leaking . I have a 1972 Dodge Demon did a brake conversion all factory parts new I have installed two new brake valves and both leak I know this one is not leaking at the lines I think at the top where the line from the master cylinder goes brass hex fitting or the hex piece goes into the valve
Thanks for reading this post Waco Demon

I am on my 3rd distribution block from online tube 1 leaked from the warning light plug and the other from the double nut leaking from around the washer I called again to inline tube they are replacing the distribution block again they told me they are having issues if this 1 leaks I'm getting my money back