Meeting is fully booked, how to notify user to book onto another day

[Mia2022]

Hello,

I am creating a Power Apps which allows user to book onto meeting at different dates, for the four choices of duration that they want (they can choose 5 mins, 10 mins, 15 mins and 20 mins). This apps is linked with a SharePoint list (as in the image below). The Duration is a dropdown option, the Duration_mins is a "number" column. I only add the Duration_mins in case the Duration does not work for my coding. 

My question is which coding should I write to enable a visible text "The meeting date is fully booked, please book onto the next meeting", when the Duration of each meeting date reaches 60 minutes. It means, when a user book onto 2/1/2022 (1st Feb 2022), if meeting duration of 2/1/2022 already reaches 60 minutes, then a pop-up text to let the user know to book onto the next meeting 2/8/2022 (8th Feb 2022). If the meeting duration of 8 Feb 2022 reaches 60 minutes, then the user need to book onto the different date. 

After the Apps is created, I added a Text Label onto the EditScreen with the text: "The meeting date is fully booked, please book onto the next meeting"

I then edit the formula of the visible properties, as the DATE is DataCardValue15, the formula I used is:

If(Sum(Duration_mins, if(Filter(TEST_booking_slots,DataCardValue15.SelectedDate in Text (DATE))))>=60), true, false)

What I want is: If filter by the booking DATE, with the same selected date, if the duration_mins >=60, then a pop-up label is visible.

 

However, errors show and it does not work, it would be great if you could show me which formula I should use please. Thank you very much!

 

[KajalGupta15]

To enable a visible text notification, you should have a meeting table over there you can set the limit for a day like day=10 meetings example  if(meetings=>10 days, Notify("Meeting is fully booked, how to notify user to book onto another day", Warning).