How to say “Thank you, but a discount doesn't fix the defect. I ask that the replacement be assessed by Friday.” in Japanese
In Japanese
ありがとうございます。ただ、割引では不具合は解決しません。金曜日までに交換をご検討いただくようお願いします。
Arigatō gozaimasu. Tada, waribiki de wa fuguai wa kaiketsu shimasen. Kin'yōbi made ni kōkan o go-kentō itadaku yō onegai shimasu.