I accidentally changed the URL to one of my campaigns (in Settings) to include the | character, which is not allowed in a URL. The link therefore seems to be corrupted somehow, the | character having been replaced by %7C. Every time the link (Campaigns drop down menu) is used, it brings you to a 'This site can't be reached.' page (DNS address could not be found).
I have contacted the OP support using the support tool, but have received no reply for several days.
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