Styling on mobile is gone after installation

Hi,

After I installed LiteSpeed Cache Plugin the website became much faster! But after a few days I noticed that the styling on mobile is completely gone. I’ve tested with some features that I turned off and on, but that didn’t work. Now I’ve set everything back to the original state so everything should be off. I even deactivated and deleted the plugin but nothing seems to help. I lost the styling of the website completely on mobile. Can someone please help me asap?

It’s about the website https://wearewuunder.com/. 

Thanks a lot in advance!

The page I need help with: [log in to see the link]

 

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