Weglot, Finsweet multi-language element not working properly

Hi there - I have incorporated Weglot into an existing commercial site and I wanted to add the @Finsweet Weglot elements to make choosing a language selection a bit more elegant.

I have got this working apart from an odd glitch where the language initials DE / EN revert to EN/ EN once I click one of the languages. It is easier to show you what is happening.

Any thoughts?

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