ORA-12516 TNS:listener could not find available handler with matching protocol stack

How to fix this problem,I am able to connect locally no users are able to connect using tnsentry ,here is the lsnrctl service output.
Instance "MSBI2", status READY, has 2 handler(s) for this service...
Handler(s):
"DEDICATED" established:46 refused:0 state:blocked
output of lsnrctl status
Service "MSBI" has 2 instance(s).
Instance "MSBI1", status READY, has 1 handler(s) for this service...
Instance "MSBI2", status READY, has 2 handler(s) for this service...
Service "MSBI_XPT" has 2 instance(s).
Instance "MSBI1", status READY, has 1 handler(s) for this service...
Instance "MSBI2", status READY, has 2 handler(s) for this service...
Thanks in advance

post the listener.ora and the tnsnames file

delete the *.dat found in $ORACLE_HOME\otrace directory.
restart the listener.