A prior pending application notification means the USPTO has identified another trademark application, filed earlier than yours, for a mark that is similar enough to yours to potentially conflict. Your application is suspended while the earlier application is being examined.
This is not an outright refusal, but more of an administrative suspension. Your application will remain active, and so will your filing date. If the earlier application is refused or abandoned, the suspension on your application is automatically lifted, and examination continues. However, if the earlier application proceeds to registration, the USPTO may at that point issue a likelihood of confusion refusal against your application. This needs to be resolved with a separate response to that specific office action.