Patching for ios

I’m using patches and DLC tests
Basically, there is no problem in the PC and the Android patch and DLC.
But when testing IOS, patching is not successful.
The patch is generated by _P.pak’s files, tested in Android and PC , and can be loaded successfully after downloading
_P.pak through Http. They all use the same path and are placed under the Paks folder. However, the use of IOS found that the load was not successful, thought it was a path problem, and therefore tested many paths, and finally failed.
Can anyone tell me why? What do you need to pay attention to in the IOS patch?