I've received a baby sleeping bag and it smells VERY strongly of Lenor Unstoppables which the previous owner liked to use. I've tried soaking it with baking soda, with vinegar, and have washed it several times. The smell has diminished but still overpowering and unbearable for me, who knows what effect this sensory overload will have on a newborn. What will be effective to remove the odour/fragrance?
You obviously have a strong opponent here - designed to stick to the fabric for weeks according to the manufacturer.
So pretend to "use" it:
Wash repeatedly, as hot and "rough" as the fabric will allow, air out as much as possible. Sun and wind will help break down and carry away scents.
In cases like these, I tend to leave the laundry outside even over night, e.g. wash in the morning, hang to dry outside, leave out over night (dew falling and drying again in the morning), repeat.
Expect the process to last a few days and of course do not use detergent with (strong) scent. Kind of obvious, but you don't want to add scent / bind the existing scent.