The two scenarios Immigration actually regulates
Immigration’s Foreign Domestic Helper rules name exactly two circumstances where a new permit application is allowed: the worker was found medically unfit after arriving, or she was approved but never entered Malaysia. Both are about the permit record, letting you apply for a new visa slot rather than restarting the entire approval process. Neither addresses what happens commercially between your household and the agency you engaged.
If your situation matches one of these two, that’s the process to follow, and it runs independently of anything an agency has promised you. This site’s dedicated guide on medical-exam failures covers the FOMEMA scenario specifically.
Everything outside those two scenarios
A placement can fail to work out for reasons that have nothing to do with a medical exam or a no-show: it doesn’t suit the household, the worker resigns early, or the relationship simply doesn’t work. None of that is addressed by Immigration’s rules or by Act 246. What happens next depends entirely on whatever commercial terms your agency has offered, which is a private arrangement, not a government-backed policy.
Since no source sets a floor here, get those terms in writing before you need them, not after. This site’s guide on what "guarantee" means when an agency uses the word covers how to evaluate that specific commercial term.