Please create the value in the picklist for this field.
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"Status: is invalid"
"The BillingStateCode/MailingStateCode field contains 'X', which isn't an available state. Your administrator can add it for you."
"Mismatched integration value and ISO code for field: Billing State/Province Code"
"Billing/Mailing Country Code: bad value for restricted picklist field: X"
API Guidelines for SaaS Partners