Edit in php.ini file
If you have access to the PHP.ini file you can directly increase the PHP Memory Limit. If you have access to the php.ini file, find memory_limit and increase its limit as memory_limit=256M
Some shared hosting servers would not give you access to the PHP.ini file. But some servers allow you to create a duplicate PHP.ini in your respective site directories which data/values will override the default php.ini values. To do that you just need to create a file with the name ‘php.ini’ in the directory in the root directory. In that php.ini file write the following code:
memory_limit = 256M
Increase memory limit in wp-config.php
Open the wp-config.php file in the root directory. Paste the following line in that file
Increase memory limit in .htaccess file
WordPress creates a .htaccess file when permalink setting. Paste the following code in the .htaccess file at the very bottom
If these solution is not working talk to your host provider to increase this value for you.