J: 3.9.25
K2: 2.10.3

I have a user that got the error "call to a member function purgeprivate() on null" when attempting to login to the site and post an article.

The weird thing is they were able to login once and post. Days later when attempting to log back in they get the error. I've even gone as far as deleting their profile, creating a brand new profile then once created the same thing happened once again. This particular user has had a user profile to post for several years now and just recently in the last two or three weeks has this started. The other users have no issues with logging in and posting nor get this error.

There are no other errors but just a page with that error listed. This has happened in both Safari and Chrome.

Bumping this back up.

I got the same error recently. I think it was due to an incorrect login, but I'm a bit baffled too.

I'm using PHP7.3 are you?

I posted here: joomla.stackexchange.com/questions/28970/0-call-to-a-member-function-purgeprivate-on-null

No, I am running 7.4. However I test 7.3 at the recommendation of my web host with no change.

I have a feeling this may be a Joomla thing not a K2 thing as I'm not using K2

For me this is from Litespeed Cache.

I went into cPanel and I went to Terminal and I did a search by copying and pasting this (right click to paste)

grep -Ri purgeprivate public_html

It returns

$this->plugin->lscInstance->purgePrivate("com_virtuemart.cart");

    
If you are also using J2Store or Virtumart or another cart, it could be the same thing. 

I opened a GitHub issue here that you may wish to follow:

github.com/litespeedtech/lscache-joomla/issues/42

Because of PHP errors?