Error when refreshing subscription after upgrading to RS 2023

Dear All,

We are getting errors like o SSRS subscritions deployed on PBI server

" The permissions granted to user '' are insufficient for performing this operation.Mail will not be resent. "

Although in the subscription itself I can see that it is said the email has been sent

In Event Viewer, that are plenty of errors like

Any Help will be appreciated

Thanks and Regards