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merchants.not_ready_for_livemerchantsRule R12The merchant does not yet meet the conditions for live mode
Live mode requires three things together: status approved (a merchant in sandbox has passed review but has not been promoted yet), at least one verified bank account, and an accepted fee plan. The response lists the unmet ones as status:approved, bank_account_verified and fee_plan_accepted.
Why the API refuses
WHEN RequestLiveMode is executed, THE SYSTEM SHALL reject it unless the status is approved (a sandbox merchant has not been promoted yet and is not), at least one bank account is verified and a fee plan has been accepted, listing the unmet conditions as status:approved, bank_account_verified and fee_plan_accepted.
What to do
Read the list — it is the checklist. A bank account that exists is not the same as one that is verified, and that is the condition most often outstanding. Test mode keeps working throughout.