appointments in 2 services are merged

I have 2 services in appointment+ (2 conference rooms) .
I just noticed that when I make an appointment in one of the conference rooms, it also block the time slot on the other conference room, for example: if I reserve 'big conference room' for April 20th from 11:00 to 12:00 , then I go to 'small conference room' (the 2nd service) , and click 'Show available times' , this time (April 20th from 11:00 to 12:00) will be blocked as well and I am not able to reserve the room. also I tried the opposite, to reserve in the 'small conference room ' at a cretin time, and it does the same, will block the time slot in the 'big conference room' .

Please help, I would like to have that the 2 services to have 2 separate time slot.