Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 16384 bytes)

I'm using Elgg v. 2.3.14 and getting the following when attempting to logon:

Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 16384 bytes) in /var/www/html/vendor/elgg/elgg/engine/classes/Elgg/Router.php on line 77

I'm having a hard time figuring this one out.  I've read up online to try to troubleshoot this issue and tried updating my plp.ini file to set ini_set('memory_limit', '256M'); (it was originally set to 128M).  

But I still get the error when attempting to login through walled_garden.  If I, however type in https://myhostnam/activity, I'm able to get into the site and interact.  Not sure why I'm getting this issue.  Has anyone else experienced anything similar?