Iphone lockscreen displaying rough edges in photo. IOS16.4

see screen shots below, when I am customising the lock screen it looks fine but the final result has very unattractive edges. This is a new issue that was not happening prior to this lates IOS update.

yes I have powered down and restarted.

yes this is a photo taken in portrait mode, however I have also tried to use a screen shot of the original image with the blur effect baked in, but that did not solve the issue.

any suggestions?

thanks.