Recovering a lost S Planner from Google

[Labrador1]

I have had problems with a Samsung J3 2016 and had to do a factory reset.  I was told that my calendar was backed up so I went ahead with this.  I have now had to purchase a new phone, Samsung A10 and the guy setting this up for me cannot find my calendar.  I am very upset that I may have lost all of the entries.   Help!