The SQLCODE -927 indicates that the application is attempting to execute a DB2 SQL statement, but the required DB2 environment is not properly initialized. Ensure that the IMS and DB2 subsystems are correctly configured to work together, and verify that the application is properly linked with the DB2 attachment module (DSNELI). Additionally, check the JCL to confirm that the appropriate DB2 region or plan is specified and active before the program executes the DB2 module.