Help with Database fields please

I am trying to accomplish a simple form,that will calculate and show a person age according the date selected in the calendar and came up with some issue that I don’t reallyunderstand

1.I get the error "birthday does not exist on dataset1
The dataset ID is correct and there is a birthday field in the dataset(written as seen there)
The datapicker on the website has the ID birthday and it is connected to the database to the birthday field

2.“text” does not exist on #ageBox , the ID of the age field is #ageBox it has the text value,and it is connected to the database to the age field.I have tried changing the value to number but I come up with the same error

Any help would be appreciated