SQL Error 1263

Importing data in Mysql DB data is personfirstname = NULL personmiddleinitial = I personlastname = Null

issue is NULL is not expected in the name field

I have checked the "Allow NULL" for personfirstname, personfirstname, personlastname

I still get the error "Column set to default value; NULL supplied to NOT NULL column 'personfirstname' at row"

any ideas

Is that perhaps MS SQL, not MySQL?