Bom Table out of sync and model dimension not able to delete

Hi all 

please find attached a model aand drawing 

there is a dimension i cannot delete 

i suspect that it is a empty sketch but please do your own look at

next the BOM is not connected to the ballons

i started with a very simple model to more or less test bom tables

rergards and thank in advance

Edu ​​​​​​​