If you encounter the error, REP-56055 exceeded max connections allowed Oracle Reports Error then you need to increased the number of database connection in the reports configuration file.
1. Goto $ORACLE_HOME/reports/conf/ , find your server report name e.g. TestReport.conf
2. find the connection maxConnect= and set it to a higher values.
3. Restart the reports services .
There is also a possibilities that after you increase to high value on the maximum database connection , the error still persists.
If so, then if your reports takes a long time to generated out and has many pages the possibilities are that the number of session in 1 reports engine more than the reports engine can handled.
Then you need to changed the engineid , engine id="rwEng" engLife="50" to lesser values such as 5 and increase your maxEngine from 1 to higher value like 5.