Glasses should be considered as medical devices, and they need factory registration and product listing before being exported to the United States.
Note: FDA has never had any certificates.
After the goods are detained, see what the report issued by FDA says and what the FDA accuses, and then decide whether to do the test. Don't expect the FDA to retest your samples. The FDA will not admit that the same sample is wrong.
According to the content of the accusation, if handled properly, it may be cleared through customs and may be included in the FDA's import alert blacklist. In the future, each ticket of goods will be automatically detained without inspection. The cost will be high then.
Two schemes: 1. If there is a problem, you can hire a lawyer to correct it according to the contents of the FDA accusation, and you may go through customs clearance. If you are blacklisted, you can delete your name.
2. Usually, a lawyer is hired to conduct a regulatory review of the factory, or consult in advance what laws and regulations need to be consulted before export, so as to avoid problems, being refused import or requiring destruction.