The money actually was taken from your retirement account. When you left the company your loan was satisfied by reducing the balance to your credit in your qualified retirement account in an offset distribution. This is equivalent to the plan making a taxable distribution to you that you immediately turn around to pay off the loan, so you received a 2019 Form 1099-R that must be reported on your tax return. The taxable amount of this distribution is also subject to a 10% early-distribution penalty unless you have an exception that applies.
If you can come up with the money to do so, you have until the due date of your 2019 tax return, including extensions, to roll this distribution over to another retirement account and continue to defer the taxes and avoid the early-distribution penalty.
