there is a leak in my roof but i cant seem to find the source. i’ve tared up alot of my roof attempting to find the leak but i havent found it. can you help me.

herts copper roof

Whenever the rain pours heavily, there is a leak buildup in the center of the ceiling. The flat wooden roof is covered in tar and we can’t isolate the problem. Are there any good roof repair/leak sealing products, and are they easy to apply?

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