Novice trying to import access database on Mac Os

I have another problem which has reared it's ugly head. Date column has dates of different lengths i.e. in some cases just the year e.g. 1836, in others year and month i.e. 1984/02 and yet in others the year, month and day i.e. 1836/03/09. I when merching my USER, one of the attributes I am adding is the date i.e MERGE (user:User {id:row.usr_id), date:date(row.date)}) and I am getting an error message that says ""Text cannot be parsed to a Date "1826/09"""". How best can I resolve the issue? is there a way YYYY/MM can be parsed as a date? the same issue occurs if I use CREATE instead of MERGE
thanks in advance?

I think this comes down to having inconsistent data representing a date. Typically a date includes date, month and year. For 1836 this simply is a number. If we were to convert to a date, even if we could, how would it be represented as a year, month, day? Is this thus January 1 or 1836? The same for 1826/09. Is that the 9th month of 1826? If so then what day of the 9th month of 1826? If not the 9th month is it 9th the day?
If this 'date' is coming from some table.column in Access how does Access interpret 1826 ???