Doesn't look like volleyball court is here, more like construction area.
Added some photos of the parking, moving from tennis courts towards Augusta Delgava iela and then one facing the tennis courts direction. There are 2 breaks in marking on parking but I still think that it should be mapped as single parking, like HellMaps mentioned. There are also some parking spots for disabled people and some bicycle parkings sticking to building mapped as B1-18. The building itself is actually not B1-18, it has 3 [double] entrances B21(1)/B22(22) - B23(3)/B24(4) - B25(5)/B26(6) counting from tennis court to Delgava iela, across the parking in question.
Also added photo of South-West gates facing them from inside (towards the Augšuela). As you can see, all gates connected to the road, not like the map shows. Notice board is on the gates from South side, it's mapped but not categorized (?).

Attached photo(s):
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https://westnordost.de/p/232125.jpg
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https://westnordost.de/p/232135.jpg