Move users from one store to another (Do not share) - Magento 2.3

[ManuelSissl]

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.

UPDATE 1:

These are my website and stores:

This is my user configuration:

[Manish Mittal]

Hello @ManuelSissl 

You can not change customer store but you can try some workarounds i.e:

1. Directly you can change from DB

2. Try with export/ Import functionality: Login in admin> export customer and change website and store code values and import again.

Try if it works for you.