The UR5e main assembly is complete, including its installed mounting adapter. The separately agreed spare adapter remains missing. I have sent the spare line and its complete assembly reference, but the seller still replies next shipment without naming stock or dispatch.
Ask whether the identified spare is physically available and what prevents separate dispatch. Keep that answer against the missing spare line, so the installed adapter does not get counted as fulfilment again.
They now say the spare is not available and offer a credit. I have asked maintenance for identified alternative supply and its delivered cost before deciding; the rest of the main package is not in dispute.
Does the offer settle only the adapter, or the entire spare kit? The wording needs to leave any other outstanding items visible when you compare the credit with replacement supply.