1. First of all, a business visa requires an invitation letter from the company. The visa is processed at the embassy.
Secondly, if there is anything wrong with the documents presented, just refuse to sign them.
3. Last valid passport: guests must sign on the last page, and if they have old passports, they must provide them (including official passports and one-year tourist passports); If you need to apply for a UK visa, you must have more than two unused visa pages.