No that is your problem for you do not exactly or precisely what year Jerusalem whether it was 586 or 587 BCE whereas WT has identified the exact year as 607 BCE and that is the very stark difference.
I'm confused (Not for the first time...)
How are Jehovah's Witnesses immune from the uncertainty inherent in the Bible itself, over the counting system in use vis-à-vis the reigns of kings?
Do not Jehovah's Witnesses themselves date Nebuchadnezzar's dream of the metal image to 606/605 BCE?