In-app Safari log-ins not showing input fields on iPhone

None of the suggested fixes worked for me - cache clearing, uninstalling/reinstalling, deleting addons, turning off content blockers - I eventually found in the Safari’s settings : Website data - in this menu I unchecked Privacy Preserving Ad Management - and I was able to log into my apps. The fields appeared after closing and reopening the app. Success!

[Edited by Moderator]

Original Title: App Log-ins not working - In-app safari log ins not showing input fields for log in details - blank pages - fixed