Error adding blocks to drawing

[Anonymous]

Hello!

I'm trying to add a block to a drawing with C#, but it crashes at the following lines:

if (bt.Has("Sensing Unit"))
{
idBTR = bt["Sensing Unit"];
}
else
{
idBTR = doc.Database.Insert("Sensing Unit",db,false);
}

The fatal error says "eWrongDatabase." Is there any reason why this line would cause that error? How can I check if I have the "right" database before running the check?

Thanks so much for any help!

-Carlos