The seal rarely leaks but I would not call it unusual if it did.
If the VVT was faulty you would have starting issues and meant DTCs
I w pulsed be surprised is a parts department stocked the seal.
I keep a couple personally but because I modify the stack valve cover and must remove the seal and the splash guards for the mods.(see pictures below)

And also in the small chance the shop needs one for a customer.

 

Thanks for the added Info.
BTW is there any Youtube video on this subject

 

Idk … don’t use it. I tend to find mistakes or incompleteness in most all of them.

 

Have a look on this site. You might find a manual for your car.

https://charm.li/

 

That's the oil filler cap and has a seal in it. Don't know if you can buy the seal seperate or with the cap.

 

Look at the picture again... in the first post then read exactly what I responded with as well pictures..... you are looking at the *wrong area and recommending the wrong part as well availability of parts.

 

I'm outta luck as I have replaced the gasket and rubber gasket for the engine cover gain a few days ago the gasket for the oil control valve and it leaky again round the gasket

Here in Oz its 400$US for the oil control valve from the stellarship Mazda Dealer

My only hope is to track down somewhere else is could it still be the gasket was faulty

 

Did you carefully look for cracked plastic around the seal area. That would be the only reason the seal would leak after you replaced it. The only other would be the electrical case on the part has ruptured but you should have gotten a DTC(check engine light).

 

I didnt check for damage

I have had a look and can see no visible damage around the oil control value or the gasket area

 

you need to remove the valve cover again to do a complete inspection. Or wipe the area drive a short distance to see exactly where the leak re appears.

The thermal plastic can crack and be un-noticeable and takes a careful methodically inspection.