I have a very simple Lego man assembly to be done, I'm having problems with the arms only. When creating a mate, two faces/entities need to be selected, in this case the arm and the body, the mate happens successfully in the beginning, but when saving the file or reopening the assembly file, one of the two selections for the mate to happen disappears causing an error, it says “one of the entities is suppressed, invalid or missing” in this case missing. I have tried to mate in all possible ways with no luck. Any solutions would be appreciated. Thanks

Edu ​​​​​​​3DEXPERIENCE ​​​​​​​SOLIDWORKS