Shop maintenance mode

Hello all,
I have to redirect the test site URL using this core \OxidEsales\Eshop\Core\Registry::getUtils()->redirect() function but its not redirected the shop was under maintenance mode error will be displayed.

Can anyone please help me to resolve this issue.

check error logs

i checked error log file, In my finalize order method it is calling default PayPal order object, is this is the reason is going to maintenance mode