0000FF berries
Hello, welcome to OpenStreetMap. 
I'm one of the OpenStreetMap volunteers. Thanks for your note https://www.openstreetmap.org/note/2970991 

I've added the studio and the entrance with https://www.openstreetmap.org/changeset/115330208 You can provide additional information, such as the level where the studio is located and its exact location in the building.

Additionally, as you have an account on www.openstreetmap.org , you can also make such changes yourself if you wish. If you have any questions, you can ask at https://forum.openstreetmap.org (in English) /viewforum.php?id=10 or at https://forum.openstreetmap.org/viewforum.php?id=27 (in Greek). Please note that you will need a separate account to access the forum. Or send me a message. 

Thanks again and happy mapping.