Unfortunately, I don't think this is possible. If this training was through the WDP program, you could report the partner, but I don't think that they will be able to directly provide you with a voucher. I would start with contacting the WDP group https://workforce.oracle.com/pls/wdp_ekit/rd_psp_contact1 within Oracle for your complaint and see if they can assist. They certainly need to know if their partners are not holding up their end of the deal. Of course, if this is not a WDP partner, you'd need different contacts. I'd need more info to guide you further.
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