Thank you for your quick response.
I tried Version 3.1.3, but it looks doesn't work on Joomla version 3.7.x.
As my Joomla template has something to do with Joomla newer version, I can not upgrade Joomla.
What is the Joomla requirement for Securitycheck pro 3.1.3 ?.
It seems your Joomla version is too old and doesn't have some classes added to give compatibillity with Joomla 4.
So let's install the previous version of Securitycheck Pro. If the problem persists then I will check what's happening. In that case please send me administrative credentials to access your backend and also ftp (use the email from which you receive forum notifications).