Import Items "Aras.Server.Core.ItemIsNotLockedException" error

Hi evreyone,

I used AML which helps to Imports the Items.
I tried the same way to import those two Itemtypes.
Just some differences of attribute and property, one of them is successful ,
however, the result of the other is mistaken. Like below:

<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:i18n="http://www.aras.com/I18N">
<SOAP-ENV:Body>
<SOAP-ENV:Fault>
<faultcode>1</faultcode>
<faultactor />
<faultstring>Aras.Server.Core.ItemIsNotLockedException</faultstring>
</SOAP-ENV:Fault>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>

Imports AML
<Item isNew="1" isTemp="1" type="Document" action="add" id="8A355B44F544466A98233EAB0C89C88A" doGetItem="0">
<classification>SOP/TEST</classification>
<name>DOCTEST</name>
<description>TestImport1</description>
<owned_by_id>F5CA9C2CCAF04DBA8B48B161344624E1</owned_by_id>
<managed_by_id>F5CA9C2CCAF04DBA8B48B161344624E1</managed_by_id>
<team_id>12BEE1A764844C54B40AB2E71729E1C1</team_id>
</Item>

Id like to know why it's going wrong. Any ideas ? 

(Is it possible that Itemtype setting made it wrong ? (e.g. : server method))

Thanks