If the developement team don't accept the defects

After executing the test cases we can report the defects to the
developement team,some of the defects were rejected by the developement team, so as a tester what we can do for that situations?

Thanks in advance.

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Whether to reject defects should not be just a development decision. It should be a business decision. Are developers alone deciding what to fix and not fix? Neither developers or testers should make that decision alone.

so as a tester what we can do for that situations？We can become an advocate for the bugs we report and explain why the bug should be fixed in terms that matter to the business.
We can also try to understand the business reasons for not fixing a bug.