@hampton123 Thanks for reaching out. If you delete the "Azure Active Directory" and "Username and Password" provider types under "Identities" in your APIM service's developer portal, they will be permanently deleted there is no option to disable and enable it as required.
In the future, if you want to use these provider types again, you will need to add them back manually.
let me know incase of further queries, I would be happy to assist you.
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