500 error in admin section with plugin installation

I just tried to install the plugin and it gives me 500 error in admin section but front end is working well. And after enabling the debugging, i got the following error of memory exhaustion. If anyone have any solution, please share it.
Thank you

Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 20480 bytes) in /var/www/html/wp-includes/class-wp-hook.php on line 287

Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 262144 bytes) in /var/www/html/wp-includes/load.php on line 1499

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