plugin.builders on "[Plugin: Waiting: One-click countdowns] Impossible to register a single countdown :("

I installed the plugin and I went to the waiting page on my dashboard menu but when I try to save my first timer nothing happens. The bouton Save became Saving and still like this.

I really would like to buy the circular one but if I cant install the free one...

If you have any solution could be great !

https://wordpress.org/plugins/waiting/

Hi, cannot say what's happening. Is it possible for you to give me access to your dashboard? Email me to support @ plugin.builders