How to Fix migrating the orders from M1 site to M2

Hi Uber Theme Team,
 
While migrating the orders from M1 site to M2 site, we received an error. We are using UB Data Migration Pro (CE) -- 3.0.9 version.
Error on step 7. Import Sales:
PHP Error[8]: unserialize(): Error at offset 664 of 685 bytes
in file pub/ub-tool/protected/controllers/Step7Controller.php at line 1846
#0 pub/ub-tool/protected/controllers/Step7Controller.php(1846): unserialize()
#1 pub/ub-tool/protected/controllers/Step7Controller.php(1491): Step7Controller->_convertQuoteItemOptionCodeValue()
#2 pub/ub-tool/protected/controllers/Step7Controller.php(1381): Step7Controller->_migrateSalesQuoteItem()
#3 pub/ub-tool/protected/controllers/Step7Controller.php(1242): Step7Controller->_migrateSalesQuote()
#4 pub/ub-tool/protected/controllers/Step7Controller.php(240): Step7Controller->_migrateSalesOrders()
#5 pub/ub-tool/protected/commands/RunCommand.php(58): Step7Controller->actionRun()
#6 pub/ub-tool/protected/commands/RunCommand.php(28): RunCommand->_migrateData()
#7 unknown(0): RunCommand->actionIndex()
#8 pub/ub-tool/yii/console/CConsoleCommand.php(172): ReflectionMethod->invokeArgs()
#9 pub/ub-tool/yii/console/CConsoleCommandRunner.php(71): RunCommand->run()
#10 pub/ub-tool/yii/console/CConsoleApplication.php(92): CConsoleCommandRunner->run()
#11 pub/ub-tool/yii/base/CApplication.php(184): CConsoleApplication->processRequest()
#12 pub/ub-tool/yii/yiic.php(33): CConsoleApplication->run()
#13 pub/ub-tool/protected/ubdatamigration_cli.php(5): require_once()
#14 bin/ubdatamigration(4): require_once()
Could you please check whether there is a bug in the extension? And how we can resolve this?

Thanks!”