What you said should be a scam message. Don't believe it. CCB did invite customers to apply for adjusting the quota recently, but there is no need for you to submit any information at all, let alone call back. If you are willing to adjust, as long as you reply according to the content of the short message, you only need to use the 4 digits of your card tail number, and you don't need to provide other information.

nowadays, many fraudulent short messages are the same as real ones, and they are sent directly through 95533, which is not entirely believed. Because scammers now use SMS sent by pseudo base stations. Baidu says this about pseudo base stations. "Pseudo base station equipment generally consists of a host computer and a laptop computer. Through SMS senders, SMS senders and other related equipment, mobile phone card information within a certain radius can be searched, and by pretending to be the base station of an operator, using other people's mobile phone numbers to forcibly send short messages such as fraud and advertising to users' mobile phones." Therefore, this is not a system vulnerability of CCB, it is just a fake base station. Pseudo base stations can forcibly send short messages to your mobile phone, and now telecom operators can't stop it.

in the future, if you are unclear, don't call back and don't click any links casually. If you have any questions, just call the customer service hotline behind the card for consultation.