So are you going to buy the car, or not? If not, then cancel the order and be done with it. If you are, refunding your money would incur administrative expenses on Tesla’s part, for no significant good reason: they’d have to mark the order unpaid, transfer funds (which they might not have on hand; they might have made payment to the USA, for example, and hence might only have minimal unallocated funds for unbudgeted expenses), and chase you for a new payment when the car is ready. (Which, by all accounts, will only be a week or two later than originally thought.)
In short, your expectations are unrealistic. Either cancel, or deal with it.