Parts ETA keeps changing

My Company Prestige auto made an order with Buffalo Toyota for parts specifically coming from Hino for a truck. Reference number *** The part was order almost 3 weeks ago and the ETA on the part keeps changing. This is holding back business on our side and the customer is starting to become aggravated as his business is also on hold. Please can someone contact us regarding this issue and get this part to us asap. Please note we also paid cash up front for a full order of over R40k.