About NTT Data offer letter release

Hi all, I've given technical and managerial interviews for the NTT Data mulesoft developer role and got selected on 24th May, 2025. The recruiter said the DOJ and further process will be informed to me by the 2nd of June but I didn't get any communication from him. When I called him he informed me he'll be sending the details by 4th June (today) and assured me I'm selected for the company. I just want to get clarity that it is common that NTT Data delays the release of the offer letter or do you think there'll be other reasons. Thank you.