That's sad
I could still access it with my editing link, but indeed the website says:
Therefore, as of 1st April 2018, ZeeMaps will limit the number of views on free maps to 100. (Free maps means maps that are not owned by an active paid plan). When you reach 100 views, your map will ‘freeze’ and it can only be unfrozen by upgrading to a paid subscription plan.
(and that means 100 views ever, not per month/year or anything - making it useless for anything much more than a temporary and not-public use)
Sadly, their cheapest non-free plan costs 20 dollars each month (or 200 a year), which is quite steep in my opinion. The alternative would be making a map on another website (either letting go of old markers and minnions, or importing them: it seems it's possible to export them from Zeemaps, though I didn't have the permissions)