Deductions & credits

Yeah, I entered all of the information correctly. Had every document from the IRS while filing , my expected return from Turbo tax was over 4,000usd checked the IRS site they adjusted it down to a measly $350.00. I downloaded the document that turbo tax e-filed to the feds, each line is accurate, how is there such a discrepancy? People complaining about 2g the feds outed me 4grand