Lost customized events on Calendar after latest update

I just updated my iphone 12 to the 18.6.2 and then to the 26.0.1. Later, I then went to my calendar to check the date of an upcoming event and I noticed that all my customized event calendars...1 for my grandson's sporting events, 1 for appts (Dr/Dentist), 1 for Vacations....etc.....were all missing. Holidays, Birthdays posted from FB and a few calendars through Gmail were still there. I have done every suggested fix without any relief; icloud restore, forced shutdown, icloud data recovery, and much more! How do I recover my customized calendars!