If for whatever reason the service you have selected is unable to book in, Whistl will return the error "No suitable service". The reason for this can range from many things including weight, value, destination, dimensions, etc. Unfortunately we are unable to be specific about which values were rejected by Whistl as this error comes direct from the Whistl system with no information otherwise.
If you happen to receive this error I recommend checking that details on your shipment are correct and that you're sending the shipment via a service that would allow the shipment to be sent.
If you have gone through all this and are still receiving the above mentioned error, please get in contact with our support team who will be happy to help