Hi, there are a lot of problems with your WordPress themes and plugins. It's really about time you fix them.
There are several themes that don't have any update data from your server. Ex: for News2 Template version: 1.9 Loading update data from GavicPro Update service... There is no data. And I've uploaded v 1.9.1. The biggest problem for me is that no contact forms work. I running on PHP7.3.16.

According to https://www.joomlart.com/forums/d/19105-2-errors-with-news2-parameter-must-be-an-array
you've updated the theme in jan 2019 but according to your download center it was updated in 2018. Regading your comment about that News2 theme is old...You don't have any new WP themes at all. Lastest theme was in 2017 or 2016.

I've checked all your files for New2 theme if they are compatible to newer php versions. And well....they are not, and there are probably more errors:

FILE: /wp-content/plugins/gk-nsp/data_sources/rss/rss.php

62 | ERROR | "$this" can no longer be used in a plain function or method since PHP 7.1.

71 | ERROR | "$this" can no longer be used in a plain function or method since PHP 7.1.

FILE: /wp-content/themes/News2/News2/gavern/classes/class.recaptchalib.php

55 | WARNING | Use of deprecated PHP4 style class constructor is not supported since PHP 7.

FILE: /wp-content/themes/News2/News2/gavern/helpers/helpers.layout.php

377 | WARNING | Function create_function() is deprecated since PHP 7.2; Use an anonymous function instead
440 | WARNING | Function create_function() is deprecated since PHP 7.2; Use an anonymous function instead
442 | WARNING | Function create_function() is deprecated since PHP 7.2; Use an anonymous function instead
835 | WARNING | Function create_function() is deprecated since PHP 7.2; Use an anonymous function instead

905 | WARNING | Function create_function() is deprecated since PHP 7.2; Use an anonymous function instead

FILE: /wp-content/themes/News2/template.contact.php

68 | ERROR | Extension 'ereg' is deprecated since PHP 5.3 and removed since PHP 7.0; Use pcre instead

68 | ERROR | Function eregi() is deprecated since PHP 5.3 and removed since PHP 7.0; Use preg_match() instead

FILE: /wp-content/themes/News2/gavern/classes/class.recaptchalib.php

55 | WARNING | Use of deprecated PHP4 style class constructor is not supported since PHP 7.

FILE: /wp-content/themes/News2/gavern/helpers/helpers.layout.php

Best regards
Andreas H. Lind