QA Analytics uses a WordPress “nonce” mechanism to avoid recording improper data.

The nonce security token is a random value and is used as a one-time password.
The token has an expiration date, and after that date, the value will cause an authentication error.

Specifically, QA Analytics only issues tokens and records data when accessed by actual users and within 24 hours.

（※WordPressCodex「WordPress Nonce」）
Reference: Differences in nonce functions used in WordPress secure processing (Anti-CSRF)

>Page cache and token expiration

The token will be output to the HTML source code.

A cached page may expire in the background while its token is still present in the HTML source code of the page. In that case, the HTML source will refer to an invalid token (resulting in an authentication error) and the problem will occur.

For example, heatmap data may not be recorded correctly or no data at all.

>How to avoid problems

It is recommended that you set the page cache lifetime to 10 hours or less.

Some people may set the cache longer to improve performance, etc., but this will cause misalignment with the nonce token and increase the possibility of problems.

If you think the error is caused by the cache, please clear the cache once.
After the cache is cleared, the HTML will be regenerated and the correct nonce will be referenced again.