County water house is over 50 but septic lines extended 30 years ago. Had septic tank cleaned due to slow drainage. Person that did septic tank said he removed a clog from one of the pipes. Since having septic tank cleaned we have had a sewage smell that would work its way through the house. The smell is worse when we flush. We can also smell the odor coming from the kitchen sink but not the bathroom sinks. 2 bathrooms and one of them is where the clog was. We have tried liquid plumber and put the septic enzymes down the commodes. What are we missing? We also did a lemon, baking soda salt and hot water trick I found on line. Nothing has worked.