Thank you Sudsy !
This was the issue indeed.
As the data type I`m collecting is Single Date , and it is saved in the format dd/mm/yyyy 12:00 am , I just realized that the repeating groups where displaying data on Current user timezone.
so basically every record was adapting this data , dd/mm/yyyy 12:00 am to the timezone of where the page was being opened. Meaning that if the reservation was made in France (GMT+2) but the repeating group was opened in i.e Portugal it would adapt to GMT+1 , meaning that the record that was registered in france as dd/mm/yyyy 12:00 am is going to be displayed in Portugal as -1dd/mm/yyyy 11:00 pm
The solution to this was to round down to day (everywhere in the repeating group where this data is used), time zone selection: Static and time zone: Paris
A bit complex, however it makes sense now and the customer is happy it’s working well now