Solution:
Sounds like you need to increase the memory limit in the wp-config.php file, https://www.wpbeginner.com/wp-tutorials/fix-wordpress-memory-exhausted-error-increase-php-memory/
I recommend no less than 750M
It’s possible there are other PHP variables like the max_execution_time and max_input_time that might also need increasing, but start with the memory limit and see if that helps.