Reports not showing/no display in Dashlet Report

Hello. I am having a problem with my Report Dashlet.

Here’s what I did. I added a dashlet in the module of report. In it’s option, I chose one report records, unchecking the only show charts , and did chose one chart, then save. Afterwards, nothing happened. The reports isn’t showing in the dashlet report.

In the console, this is the error.

In the php error, there is a fatal error.

In connection with the php error, this is the code location of the fatal error.

PS. My versions are:
SuiteCRM 7.13.1
PHP 8.1, 8.0, and 7.3 (which means, I tested these three versions)
Apache v2.4.53

Thank you in advance

Already fixed. I just added a condition before this syntax runs.

if(!empty($req['parameter_value']))

It would be interesting to create a PR with this fix on Github.