Hello @semaja ,
I would recommend to use "<LocalizedString ElementType="UxElement" StringId="button_cancel">Cancel</LocalizedString>" in "SelfAsserted-ProfileUpdate" in localization policy.
This will give the user to cancel and take user step back to choose email as MFA option.
Also please try extension policy as per https://github.com/azure-ad-b2c/samples/blob/master/policies/mfa-email-or-phone/policy/SignUpOrSignin_PhoneOrEmailMFA.xml , where user will have option to choose MFA via email or phone.
Please do let me know if you have any queries in the comments section.
Thanks,
Akshay Kaushik
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