COPS-PR Report message clarification

Hi,
Can somebody give an explanation for the following...?
May look like and old one, but still need to get a clear solotion. In a
COPS-PR report message, why do we need to have [0-*] multiplicity for Client
SI object, since there can be only one report type at a time.
[Ref: rfc 3084]

Also, can someone give a illustration for the above object being used in
COPS-PR Report message. for example, a detailed error report.

Regards
Wilson
http://www.wsspl.com