Can I file another H&C application after an earlier one was refused?

Yes, generally there's no absolute bar on filing another H&C application after an earlier refusal, and people do this when their circumstances have genuinely developed since the last decision. But simply reapplying with substantially the same facts and arguments that already failed is unlikely to produce a different result, since the underlying picture the officer would be assessing hasn't meaningfully changed.

What tends to matter is genuine new development: additional time and deeper establishment in Canada, a child who has grown older with more entrenched ties, new health considerations, or other significant changes since the earlier refusal. A new application should clearly show what's different now, rather than simply restating the earlier submission with an updated cover letter.

Because H&C applications require significant time, evidence-gathering, and a filing fee, and because a weak repeat application can reinforce a pattern of unsuccessful attempts rather than genuinely improving the odds, anyone considering another H&C application should have their situation reviewed by a lawyer first to assess whether enough has genuinely changed to justify trying again, rather than reapplying reflexively after every refusal.