When a wool wrap changes significantly from loom state after washing, that doesn’t necessarily mean that it is felted. It is okay for a wrap that is 50% wool to feel- woolly!
The brand new wrap that you receive is still in its ‘unfinished’ state- the wool still has the natural processing oils in it that keep it tight and smooth during weaving. washing those out allows the wool to bloom and become fluffy and soft. This may also naturally decrease the width of your wrap and lose some of the definition of the individual fibres, but again that doesn’t make a wrap ‘felted’. If your cloth still has the wrapping qualities needed to tie it safely and comfortably, then it is still usable. A felted wrap will be pretty much unusable. If you aren’t sure whether your wrap is felted then it probably isn’t, because when it IS felted, you know about it straight away!
This video should hopefully offer a few insights into felting and why you shouldn’t be too concerned about your lovely, fluffy wrap!