1.6tdci oil leak

[Dimi1232]

Hello, I have an oil/fuel leak around the injectors, and it's dripping down on the gearbox. So far I have changed the rocker cover gasket, injector seals, and intake manifold. The rocker cover gasket was changed by me so I can be sure that it's done correctly. The intake manifold and injector seals were changed by a mechanic, he said that he changed the bottom injector seals because those were leaking. The leak is still here, does someone have a clue about what could be the problem?

[Huskyxantia]

Look lower, drive shaft oil seal ? Core plug ?