Is the invitation letter for bank credit card application credible?

I received a credit card application message from the bank. The following are several situations, respectively.

First of all, do you do business with this bank? For example, if you have never done business with CITIC Bank, it is impossible for it to send you an invitation message. Therefore, any business invitation message sent by a bank that has no business dealings can be judged as 100% false.

Second, you have business dealings with the bank, and the invitation message is a series of numbers. Look at the last five digits. True if the last five digits match the bank number. For example, the number106 * * * 95599 invites you to apply for a credit card of ABC, and the customer service number of ABC is 95599, so the invitation is true.

Third, if it is a string of numbers with a messy mantissa, it is an invitation message sent by the platform. 100% off, that is to say, an application website for you to try yourself. If you have applied, the platform is also drawn.