Appointments+ won't show time slot / unclickable

greetings to you all.

After having nearly finished my settings for the Appointments+ plugin(time, workdays, holidays, services, service providers) I encountered one last problem that made me have to reset and reinstall the plugin - to no avail.
I used to be able to see the timeslots and also used to be able to click and book them. Now the [app_monthly_schedule] only shows the timeslots when I advance to the next 2+ months. Even then, the timeslots are not clickable, meaning I cannot do any bookings.
I have tried to see if the problem persists on the other browsers (Chrome, Safari, Firefox..) and it does. Therefore I am writing you guys on the support to see if one of my configurations is wrong or if there is a new bug with the plugin that I am not aware of.
Like I said, it used to all work like a charm. Now the app-confirmation is not even showing.

Best regards,