Error Warning: strpos() expects parameter

Hello, im testing your plugin in a site that is hosted in a CloudServer in SiteGround.
In the compatibility tab im getting this error:

Warning: strpos() expects parameter 1 to be string, array given in /home/xxx/public_html/wp-content/plugins/flying-pages/settings/compatibility.php on line 22

https://drive.google.com/file/d/1cIQW5IYiqX2CzOAXcZzuw9PrSk6L8Elk/view?usp=sharing

Any ideas how to fix this?
Thanks

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