USING TWIGIFY – Migrating drupal 7 theme to drupal 8

I am migrating an existing Drupal 7 theme to Drupal 8 using Twigify along with Drush.
While the tpl.php templates being converted into html.twig ones , an error is coming while the page.tpl.php is being converted into its twig equivalent.
The error is: Fatal error: Out of memory (allocated 1947992064) (tried to allocate 36 bytes) in on line 407

I also increased the memory limit in php.ini file from 1024M to 2048M but still the same error is coming.

Also , I tried to remove this page.tpl.php from the existing Drupal 7 theme and then tried to twigify to Drupal 8 , then the process was complete.

Can anyone help why is this error coming? Is it really a memory issue or there is something wrong with page.tpl.php or any other aspect which I am not aware of ?

Any help would be appreciated.

Thanks in advance..!!

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