
A refusal ends that basis of stay and you must address the reason or leave; to keep status continuously you must apply to renew before the current permit expires.
If your application is refused, the decision will state the grounds, and you cannot work or reside on that basis. Depending on the reason you may be able to correct the issue and re-apply, but you should not assume you can simply stay while you decide.
If you already hold employment residence, do not let it lapse. You apply for renewal before the current permit expires, submitting updated employment and supporting documents. Letting the permit expire can force you to start over and can interrupt the continuous residence that counts toward longer-term status, so diarise the expiry date well in advance.
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