Hi there, Did you read up on how to make you acetone anhydrous? That is crucial if you do not want to lose a lot of your MDMA in the wash.
You can purify after the acetone wash if you cool down a saturated solution of MDMA in IPA and filter the crystals out of the liquid, but that means losing some product.
If you are not ok with loss of product just take the clean MDMA powder, dissolve in minimal amount of IPA or ethanol or even water and leave it to dry on a container that will be easy to scrape, as the crystals are likely to stick to the bottom.