Why XML failed to add multiple tags?

[rangex]

I have created XML from ruby on rails code and i validate it with XSD file(UTF-16 encoding).In XML when i insert single name it works but for the multiple name it raise error for example\[code\]<groups> <name></name> </groups>...........It's working fine<groups> <name></name> <name></name></groups>...........It's raise error\[/code\]"FAILED: Error: Element 'name': This element is not expected. at :107."So is there any restrictions for inserting multiple tags in XML.Please help me.Thanks in advance.