Oil leaking problem (EU)

Hello so i have Audi a4 allroad b8.5 2015, 190hp 145kw, so i ahd to replace the engine bicause the exhaust valve broke and it made a hole in the piston and i hav to replace the turbocharger, so the problem is that when i drive in the city the smoke from burned oil comes in the cabin and on the highwas not bicause oil is dripping on the exgaust but the turbo is not leaking and cranmcase is not leaking and also there is no sesor that would leak and i cand find the problem after half year of searching it with my mehanic and it is not dripping much, did anyone had the same priblem ?