If you have a Roth account in your 403(b) plan, then you probably have two accounts: one Roth (after-tax) and another pre-tax.

Any contributions that are pre-tax (the amount with code "E") cannot be deducted elsewhere on your return because you already derived a tax benefit (it was removed from Wages in box 1 on your W-2).

You can't deduct Roth contributions, because they are meant to be after-tax.

So, you need to enter your W-2 as is, but I don't see a reason to change your return.