I’m not sure if they’re online yet, but I’d be happy to give you some information!
TL;DR: In Chrome, the hearts in the GUI representing health don’t change, even though the health value is changing in the backend. Changing it to work like stars and cash might fix the problem.
I wrote more thoroughly on the bug below; however, it’s a bit much, and you mentioned English isn’t your first language, so the summary above should be much easier to read and understand. In case you’re interested in reading the section below, though, I’ll put the key parts in bold to help speed up the process a bit.
Full report: When played in a Chrome browser, the health GUI doesn’t change, staying at 14 hearts instead of changing when your health value changes. This is not tied to any wave, route, or enemy, is unaffected by speed or auto, and cannot be fixed via user input (including reloading the page
We know that the health value itself does change, as evidenced by Rampardos’ damage and the fact we can still fail rounds; the only problem is that the health value is not reflected in the GUI.
Changing the value to a number and having it update in the same way stars and money update might fix the issue, as those two values update as intended.