About users who can not login to piwik

【Environment】 PC: Windows 7 (JP), Google Chrome 62.6.3202.92, Firefox 52.5.0

We are building a Piwiki server on the intranet.
When a certain user accesses from Google Chrome, Firefox, the message “Response time is too long” is displayed and Piwiki server login can not be done.
Both Google Chrome and Firefox deleted the cache, but it does not improve.

The event is that user only and not happens to other users.
Please teach us how to deal with it.

Hi,

Is it possible that Piwik tried to archive the data and PHP runs into an an timeout?

Although the cause is unknown, there was a message that the user improved it.