Hi Khai,
Appointments that are recurring but extend longer than one year can cause problems.
Microsoft recommends that you have these appointments re-occur for one year only and then set up the re-occurrence again.
Does OUTLOOK set limitation on recurring appointments which requires - Microsoft Community
After my tests, this is indeed the case:
1.More than one year:
One day of appointments per week repeated 60 times, latest will be more than one year.

The total number of appointment is 54, The date of the last appointment is 9/2/2022.

2.Within one year:
Two days of appointments per week, repeated 60 times, latest will be in one year.

The total number of appointment is 60, The date of the last appointment is 3/18/2022.(Within one year)

Regards,
Leah Ju
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