Endnote doesn't recognize the author's middle name when it is written like Rivera, AC

As I am about to submit our article we got into trouble that the endnote doesn’t recognize the middle name, for an example, there are many references that have author’s name written as Rivera, AC. Here A is the initial for first name and C is the initial of the middle name. According to my output style setting, I need to get

Rivera, A. C.;…

but endnote gives me

Rivera, A.;…

The middle name is skipped! how can I fix this? thanks

In the record, there have to spaces between initials.  Otherwise, Endnote treats it as it would if you wrote out the name and abbreviates it.  Endnote will remove the space in the output according to the output style, which can be with full stops or space or no space.