I did my taxes it said my federal refund was 4205.00, upon trying to complete the federal refund dropped to 4151.00..

[xmasbaby0]

We cannot see your screen or your tax return.  We do not know when "it" said your federal refund was $4205 or what you were doing when it dropped to $4151-- a difference of $54.    When and where were you seeing $4205?    Were you seeing a combination of a federal refund and a small state refund, perhaps?  Or when you added a new piece of information before filing, did the refund drop?   

[rjs]

What are the amounts on your Form 1040 (or 1040-SR) lines 34, 35a, 36, and 38?

Did you select the option to pay your TurboTax fees from your federal refund?

[VolvoGirl]

See if there is a penalty on 1040 line 38.  You can have a penalty even if you are getting a refund.  It happened to me one year.