Aloha,
First, do what @eviltane mentioned and I quoted. Check to see if you have enough duplicates sitting on a collection to complete other parts of that collection. The next thing is.
And then check if any of these can cover you. Which collection are you unable to get parts for? Are you meaning the ship specific collections?
Mahalo,
-Hapa
So the "Shipbuilding" Collection was for the dockyard event this past Christmas, currently, there is no way to complete this one right now. This doesn't mean that you won't have the chance.
The second was for the release of the Italian Cruiser line, currently, those containers are unavailable. These containers could become available in the future, but I cannot comment on content we haven't announced yet.
The third is the Azure Lane collection, which is currently greyed out, you cannot collect until you "enable" it.
Mahalo,
-Hapa
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