perhaps the form was noy required to be filed.  here are the rules

File Form 8606 if any of the following apply.
• You made nondeductible contributions to a traditional IRA for 2018, including a repayment of a qualified reservist distribution.
• You received distributions from a traditional, SEP, or SIMPLE IRA in 2018 and your basis in traditional IRAs is
more than zero. For this purpose, a distribution doesn’t include a distribution that is rolled over (other than a
repayment of a qualified 2017 disaster distribution (see 2018 Form 8915B)), qualified charitable distribution,
one-time distribution to fund an HSA, conversion, recharacterization, or return of certain contributions.
• You converted an amount from a traditional, SEP, or SIMPLE IRA to a Roth IRA in 2018.
• You received distributions from a Roth IRA in 2018 (other than a rollover, recharacterization, or return of certain contributions—see the instructions for Part III)
• You received a distribution from an inherited traditional IRA that has a basis, or you received a distribution from an inherited Roth IRA that wasn’t a qualified distribution. You may need to file more than one Form 8606. See IRA  with basis under What if You Inherit an IRA? in Pub. 590-B for more information.