Error 500 in checkout

[jhon]

Hello,

I have the following error when a customer already registered, tries to make a purchase again (attach screenshot):

500 Server Error

Oops, something went wrong.
Try to refresh this page or feel free to contact us if the problem persists.

It happens to me when old customers want to make another purchase, but if you are a new customer, this doesn't happen.

I have also activated the prestashop Debug to see what happened and shows me the following:

ContextErrorException in 30ca0c2dc955c78d2348997630e8d06fb312702b.file.404.tpl.php line 264:Notice: Undefined index: languages

in 30ca0c2dc955c78d2348997630e8d06fb312702b.file.404.tpl.php line 264

at ErrorHandler->handleError('8', 'Undefined index: languages', '/home/theme_name/www/app/cache/dev/smarty/compile/layouts_layout_full_width_tpl/30/ca/0c/30ca0c2dc955c78d2348997630e8d06fb312702b.file.404.tpl.php', '264', array('_smarty_tpl' => object(Smarty_Dev_Template))) in 30ca0c2dc955c78d2348997630e8d06fb312702b.file.404.tpl.php line 264

at content_5d15fdbdb7fb59_21190581(object(Smarty_Dev_Template)) in 30ca0c2dc955c78d2348997630e8d06fb312702b.file.404.tpl.php line 111

at content_5bffa50fd2ecf3_47536772(object(Smarty_Dev_Template)) in smarty_internal_templatebase.php line 188

at Smarty_Internal_TemplateBase->fetch('errors/404.tpl', null, 'layouts/layout-full-width.tpl', object(SmartyDev), false, true, false) in SmartyDev.php line 41

at SmartyDev->fetch('errors/404.tpl', null, 'layouts/layout-full-width.tpl') in FrontController.php line 661

at FrontControllerCore->smartyOutputContent('errors/404.tpl') in FrontController.php line 645

at FrontControllerCore->display() in Controller.php line 225

at ControllerCore->run() in Dispatcher.php line 379

at DispatcherCore->dispatch() in index.php line 28

Can anyone help me solve this problem? I try everything and nothing...

Thank you in advance.

Edited July 4, 2019 by jhon (see edit history)