Database connection problems, ORA-01034: ORACLE not available ORA-27101: shared memory realm does no

When I am configuring the database on SoapUI NG I got the following message

"ORA-01034: ORACLE not available ORA-27101: shared memory realm does not exist Linux-x86_64 Error: 2: No such file or directory Additional information: 3640 Additional information: -1160987969"

I have this version of ORACLE DB

NLSRTL 12.1.0.2.0 Production
Oracle Database 12c Enterprise Edition 12.1.0.2.0 64bit Production
PL/SQL 12.1.0.2.0 Production
TNS for Linux: 12.1.0.2.0 Production

any ideas?