My federal credit on Turbo tax shows $3550 while its only $735 on Sprintax which is free for me but tax filing through TurboTax is not. What do I do?

If you are a non-resident alien and you are using sprintax to file a 1040NR, what are you doing using TurboTax, which cannot prepare a 1040NR?

Is one giving you 2,800 for the Recovery Rebate Credit and the other is not?

Look at your 1040 line 30. 

Did you receive the third stimulus payments?