My new massonary fireplace leaks smoke and odor into the house

there does not seem to be a pattern that i can find yet.

here's the info I know

52x32 front opening
2 feet deep
It has ash shoot near the back of the firebox

damper is cast iron and is 6X39 it is installed on an angle if that
matters

Aprox its 41 inches from the floor of the fireplace I have a metal
rack
so wood is a few inches higher

there is 8 inches from the font of the opening to the top of the
angled damper

the flue tile is aprox 13 x 17 outside dimensions. I do not know how
large the
smokebox is but when I look into the fireplace it does angle up to the
flue

at first I thought it was cold flue and only leaked when first started
but yesterday
it leaked during the whole fire and you get the smell in the house.
its not like it pours into the
room most does go up the flue. I did the tin foil test but not sure I
did it right and lowered the opening
like 12 inches and still leaked but not sure i did it 100% right. I
think the top of the chimeny is 3 ft higher than the roof but not
sure, the fireplace is on an outside wall is aprox 23 ft high.

I am looking for a sweep in my area of NC, but till then I was looking
for some guidence and to see if
the thing is even constructed properly. Is the flue too large etc.

thanks so much and I will provide more info if I can.