Promise

The verb 'to promise' has a final syllable with the sound of the short '-i-', as in 'it', 'is' and 'in': 'PROM-iss', IPA: /'prɒ mis/. So the spelling remains -ise.

The spelling with -ise "is compulsory" (Burchfield's Fowler, s.v. -ise).

You may also be looking for advice on the typo Premise - promise.