
Welcome to Stamp Community Family, Waltini!
In the top picture, the stamps are either overinked or the plate was dirty. Although not common, it does occur more often than normal on Danzig stamps.
In the 2nd picture, the stamp is NOT a double surcharge. It is a double overprint, in which one of the overprints is a surcharge -- or more appropriately, it is a surcharge on an overprinted stamp.
In the bottom picture, the DM overprint indicates official usage. Your stamp is Danzig #O28(1922) in the Scott catalog.

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