Hi, 
The tag addr:floor=G is incorrect here. The address of the Miu restaurant doesn't contain a floor number. 

When a floor number is included in an Amsterdam address suffixes like -H, -I, -II would be added to the housenumber. These shouldn't go into separate tags and shouldn't use made up English abbreviations.

In this case the tag level=0 is the correct way to denote the restaurant is at the ground floor.