You can supplement the notice. For further information, please call 95522 for supplementary information. Be sure to call 95522.
If Taikang fails to take action within 30 days after the supplementary notice, it will cancel the right to refuse insurance.
If the insurance company does not find it after two years of underwriting, it must be underwritten.
Refer to Article 16 of the Insurance Law.
In addition, in view of your situation, I suggest not to make supplementary notification. Because I know the insurance process of Taikang health contract. This is the salesman's fault, which has nothing to do with you (provided that he doesn't ask you health questions). Even if they know, they can't refuse insurance. Another advantage is that your last extension was in Taikang, and this time they didn't refuse insurance, which can fully explain their work mistakes from the evidence.
We can talk in private.
Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.