Thanks for your reply Ed Ford, but i don't think so this issue is related to our server link. This app we have put on our server since more that 2 years and from that link our customers are downloading and installing the app. As this is enterprise account app so after installing the app user has to Trust the certificate from their iphone then they are able to use it. Also user's having ios 17 or below OS are able to download and install the app successfully from the same server link and they are still using the app. Only issue happening with iOS 18 and above versions. User's haveing iOS 18 or above not able to use the app.