Yeah, me too. It really isn't correct. The sentence is taught in the Past Perfect skill, and the solution in English is in the simple past tense. Unfortunately we cannot edit the taught sentences until we can edit the entire tree, only the solutions and translations.
EDIT: Yes I can! "Had you called the office" is now the best translation, just like "Havde du/I ringet til kontoret" is the best one in Danish. Also, "Did you call the office?" and "Ringede du/I til kontoret?" are removed, as they aren't correct. I didn't know that we could do that, haha. As a side note, I wasn't a contributor when the tree was created, I was "hired" to get the reports under control back in February :) A big thank you for notifying me about this sentence again !