Perhaps there was some confusion about what @bruce-meyers is referring to.

Interpreting the question as follows:

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I bought a bond which had accrued interest in it before I bought it.  My broker said to reduce interest income by the amount of this accrued interest when I file my tax return.  Is that OK...

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Yes, with some restrictions in how it is done.

Accrued interest is entered to reduce bond interest, but only in the tax year, that you, the purchaser first receives interest from that purchased bond.   (not including zero coupon bonds here..someone else will have to discuss that if the question comes up)

.......So if you buy a bond in November of 2017, that pays out its next interest payment in (say) Feb of 2018...then you have to wait until your 2018 tax return (in early 2019) to reduce the interest received from that bond,

.....IF you buy a bond in November of 2017, and it pays it's next interest in December of 2017, then you can reduce the interest received by the amount of accrued interest that was in the bond at the time you bought it in your 2017 tax return.

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How you do that with TTX can be a bit confusing.   For the year you are reducing the interest received, you will get a 1099-INT from the broker that shows the full amount in boxes 1,3,or 8 (depending on what bonds you hold).  Then on a page that follows the main form in the software, there is a checkbox page where you need to check the box for "I need to adjust the taxable amount"  (even if box 8 is involved)...and on a later page you will be given a box to enter your accrued interest, and make a selection to indicate "My accrued interest is included in this 1099-INT" .  That will subtract the accrued interest in your tax forms

.....BUT.....a problem if you have a 1099-INT with a mix of boxes 1,3 & 8 on it.

For any 1099-INT that has a mix of box 1,3 & 8 $$ on it.  In that case any accrued interest being reported needs to be broken out into its's own 1099-INT.....i.e. box 1 (and box 11) with it's own accrued interest, or box 3 (and box 12) with it's own accrued interest, or box 8 (and box 13) with it's own accrued interest.   Thus, with a consolidated/mixed 1099-INT, you might need to create a separate 1099-INT from that broker for the interest type for which accrued interest is being reported.