Why won't CRA accept my spouse's return on netfile ? Keeps giving #90121, NA, NA response even though my netfile worked.

According to CRA's NETFILE error guide, #90121 is related to the amount on line 121: interest and other investment income amounts.

Double-check any entries made in your spouse's return for T5 slips, T3 slips and T5013 slips.

If you can't track down what might be off, please give us a call: https://turbotax.community.intuit.ca/replies/3152013