While restarting weblogic applications it was showing below error and the application was going to Prepared state. In logs there was nothing specific which would point us to the cause of error. After doing some research we finally found that if the admin server queue is full with some pending request then it will not allow the managed server applications to come into active state.
weblogic.management.ManagementException: [Deployer:149196]Rejecting start request for application ProjectsFinancialsApp because stop request is running for the application.Errors were encountered while performing this operation.
To solve this issue, you have to restart the admin server along with all the managed servers too and make sure you clean the tmp and cache before starting all the servers or the entire domain.
After you restart it clears the command queue in admin server, after that the application startup shall work and the application will come back to ACTIVE state .