Hi Mauricio,
Have you tried this method?
Clearing Manually Entered Controller Information
When you need to move your access point to a different location in your network, you must clear the manually entered controller information to allow your access point to associate with a different controller.
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Note This command requires the controller-configured Enable password to enter the CLI EXEC mode.
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To clear or remove the manually entered controller information, you can use these EXEC mode CLI commands:
clear lwapp ap ip address
clear lwapp ip default-gateway
clear lwapp controller ip address
clear lwapp ap hostname
Manually Resetting the Access Point to Defaults
You can manually reset your access point to default settings using this EXEC mode CLI command:
clear lwapp private-config
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Note This command requires the controller-configured Enable password to enter the CLI EXEC mode.
From this doc;
http://www.cisco.com/en/US/products/ps5861/products_installation_guide_chapter09186a008072151f.html#wp1076073
Hope this helps!
Rob
