I had a store and many customers. Now I have 3 website with 1 store and i store view per each website, but when I edit a customer, the option to change stores is disabled as you can see in the image below. How can I move these users to other stores?
NOTE:
My users can only buy in one store, I must not share users in my three stores.
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UPDATE 1:
These are my website and stores:
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This is my user configuration:
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