If this was the first money that went into the designated Roth account in the plan, the 5-year period begins on January 1, 2023. Until the 5-year period has been met (and you have reached age 59½, which you have), any distribution from the designated Roth account is a proportionate mix of nontaxable conversion basis and taxable earnings.
The plan is responsible for reporting the correct taxable amount in box 2a of the Form 1099-R and the nontaxable amount in box 5. (I assume that the Form 1099-R has code 7B in box 7.)
You would also have received a code G Form 1099-R that reports the In-plan Roth Rollover that you must report on your tax return.
