TIMEZONE IS WELL CONFIGURED BUT TIME SLOT ARE NOT ACCURATE IN FRONT BOOKING PAGE

Hi,
I have some issues with the plugin.
I have configured the booking range from 10 am to 6 pm from Sunday to Thursday. But on front booking page slot are not correct and allow customers to select only 4 pm or 5 pm.
The day range is correct.
Also, availability is checking all the time without ending, and it is not possible to go on the next step as availability checking is running
I have checked the time zone as you ask in your help article, and change UTC by the city to remove conflict and set all services with the same time ranges, but nothing has changed. Still not possible to use the booking system into the website!

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