Error 500 when adding personnalized link to menu

Since a few days, i can’t add items to my menu, it perma load and then give me a 500 error ! i did use both

define( ‘CONCATENATE_SCRIPTS’, true );
define( ‘WP_MEMORY_LIMIT’, ’64M’ );

To upgrade that without success !

And it seams my logs are telling me that it’s comming from several request from megamenu :

[30-Nov-2021 19:59:53 UTC] PHP Notice: Trying to get property ‘theme_location’ of non-object in /home/undefii/www/wp-content/plugins/megamenu/megamenu.php on line 445
[30-Nov-2021 19:59:53 UTC] PHP Notice: Trying to get property ‘before’ of non-object in /home/undefii/www/wp-content/plugins/megamenu/classes/walker.class.php on line 174
[30-Nov-2021 19:59:53 UTC] PHP Notice: Trying to get property ‘link_before’ of non-object in /home/undefii/www/wp-content/plugins/megamenu/classes/walker.class.php on line 188
[30-Nov-2021 19:59:53 UTC] PHP Notice: Trying to get property ‘link_after’ of non-object in /home/undefii/www/wp-content/plugins/megamenu/classes/walker.class.php on line 188
[30-Nov-2021 19:59:53 UTC] PHP Notice: Trying to get property ‘after’ of non-object in /home/undefii/www/wp-content/plugins/megamenu/classes/walker.class.php on line 200
[30-Nov-2021 19:59:53 UTC] PHP Notice: Trying to get property ‘theme_location’ of non-object in /home/undefii/www/wp-content/plugins/megamenu/megamenu.php on line 445

i got something like 3000 lines of megamenu trying to catch something

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