Newsletter2Go Script in PopUpBuilder

Hi,
I have tried to create a pop up with the script from a German newsletter provider.

On first Previews everything seems fine, but after a while, the pop up is reduced to minimum size. Any idea what might be wrong?

This ist the script:

<script id="n2g_script">
!function(e,t,n,c,r,a,i){e.Newsletter2GoTrackingObject=r,e[r]=e[r]||function(){(e[r].q=e[r].q||[]).push(arguments)},e[r].l=1*new Date,a=t.createElement(n),i=t.getElementsByTagName(n)[0],a.async=1,a.src=c,i.parentNode.insertBefore(a,i)}(window,document,"script","https://static.newsletter2go.com/utils.js","n2g");
n2g('create', 'up3k0l3r-5fidlwwz-1bmj');
n2g('subscribe:createForm');
</script>

Thank you for your help

Kind regards
Birgit

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