This the full error from the log file :
Starting to do final processing in post-conversion. Number of threads used: 1
15.12:28:43:584;V001;F;09999 SQL text is SELECT mst.mst_snp_refresh_s.nextval FROM dual;
Connection ID is 1. Connection session ID is 1, serial number is 26443.
Exception error code is 2289.
Exception call stack is
java.sql.SQLSyntaxErrorException: ORA-02289: sequence does not exist
at oracle.jdbc.driver.T4CTTIoer11.processError(T4CTTIoer11.java:494)
at oracle.jdbc.driver.T4CTTIoer11.processError(T4CTTIoer11.java:446)
at oracle.jdbc.driver.T4C8Oall.processError(T4C8Oall.java:1054)
at oracle.jdbc.driver.T4CTTIfun.receive(T4CTTIfun.java:623)
at oracle.jdbc.driver.T4CTTIfun.doRPC(T4CTTIfun.java:252)
at oracle.jdbc.driver.T4C8Oall.doOALL(T4C8Oall.java:612)
at oracle.jdbc.driver.T4CStatement.doOall8(T4CStatement.java:213)
at oracle.jdbc.driver.T4CStatement.doOall8(T4CStatement.java:37)
at oracle.jdbc.driver.T4CStatement.executeForDescribe(T4CStatement.java:733)
at oracle.jdbc.driver.OracleStatement.executeMaybeDescribe(OracleStatement.java:904)
at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1082)
at oracle.jdbc.driver.OracleStatement.executeInternal(OracleStatement.java:1737)
at oracle.jdbc.driver.OracleStatement.execute(OracleStatement.java:1692)
at oracle.jdbc.driver.OracleStatementWrapper.execute(OracleStatementWrapper.java:300)
at oracle.duma.data.util.SQLUtil.execute(Unknown Source)
at oracle.duma.data.util.SQLUtil.execute(Unknown Source)
at oracle.duma.data.conversion.DBConversion.executeConversionSQL(Unknown Source)
at oracle.duma.gui.conversion.model.step.PostConversionModel$PostConvService$SQLExecutor.call(Unknown Source)
at oracle.duma.gui.conversion.model.step.PostConversionModel$PostConvService$SQLExecutor.run(Unknown Source)