Change a customers contract to the supplied contract code.
Response Code | Fault Code | Fault | Suggested User Message
------------- | ---------- | ----- | ----------------------
400 | 90029 | InvalidStateForCrossgradeFault | Contract cannot be crossgraded
404 | 90041 | NoContractFoundFault | Contract ID does not exist
400 | 90018 | InvalidCrossgradePathFault | Contract cannot be crossgraded to this item
400 | 90077 | VCNCurrencyMismatchFault | Viewing Card is not set for provided currency
400 | 90063 | UnableToCrossgradeFault | Crossgrade cannot be completed
400 | 90079 | VCNRequiredFault | A Viewing Card is required for this purchase
400 | 90045 | PaymentAuthorisationFault | Payment attempt failed
500 | 90050 | PaymentSystemFault | Payment collection cannot be attempted at this time
400 | 90031 | InvalidVCNFault | Viewing Card provided is Invalid
500 | 90061 | SystemFailureFault | System Failure, Please try again later
400 | 90078 | VCNInUseFault | This viewing card is already in use on another record
404 | 90022 | InvalidDiscountCodeFault | Discount does not exist
post https://virtserver.swaggerhub.com/singuladecisions/contracts/1.0.19/customer//contract//change