As of January 31, 2017, in order to sign in to WooCommerce.com you need to create and/or connect a WordPress.com account.
This is just one of the by-products resulting after WooCommerce’s acquisition by Automattic. However we have been assured that there is no change to where your information is stored or who is managing it, and you will be able to access all of your WooCommerce’s purchases, and full purchase history.
Additionally, you will have access to services useful to eCommerce like CDN, spam protection, and backup via Jetpack, all thanks to a closer integration between WooCommerce and the rest of Automattic’s products.
More info at:
https://woocommerce.com/2017/01/woocommerce-requires-wordpress-account/
More info on how to use WordPress.com to log into WooCommerce.com, connecting and accessing both sites with one single login/password:
https://docs.woocommerce.com/document/log-into-woocommerce-com-with-wordpress-com/
Now I cannot login to my woocommerce account any more after this change.
I tried everything, do you know what’s going on?
Terry, they have listed the steps for logging in here:
https://docs.woocommerce.com/document/log-into-woocommerce-com-with-wordpress-com/