I am using M2E Pro and sometimes Magento shows me an error stating that invoice or shipment is not created.
Error for invoice creation: Invoice was not created. Reason: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '53000000066' for key 'UNQ_SALES_FLAT_INVOICE_INCREMENT_ID'
Error for Shipment creation: Shipment was not created. Reason: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '53000000001' for key 'UNQ_SALES_FLAT_SHIPMENT_INCREMENT_ID'
May I please know how can I solve these errors?