Hi Kavitha,
one of my team member (Ranjitha) has altered your XML and tried importing it got imported successfully,
please find the changed XML below,
<eConnect xmlns:xsd="www.w3.org/.../XMLSchema" xmlns:xsi="www.w3.org/.../XMLSchema-instance">
<IVCreateItemPriceListType>
<taIVCreateItemPriceListLine_Items>
<taIVCreateItemPriceListLine>
<ITEMNMBR>SAMSUNG</ITEMNMBR>
<CURNCYID>Z-US$</CURNCYID>
<PRCLEVEL>EXTPRCLVL</PRCLEVEL>
<UOFM>Each</UOFM>
<UOMPRICE>20</UOMPRICE>
</taIVCreateItemPriceListLine>
</taIVCreateItemPriceListLine_Items>
<taIVCreateItemPriceListHeader>
<ITEMNMBR>SAMSUNG</ITEMNMBR>
<UOFM>Each</UOFM>
<PRCLEVEL>EXTPRCLVL</PRCLEVEL>
<CURNCYID>Z-US$</CURNCYID>
</taIVCreateItemPriceListHeader>
</IVCreateItemPriceListType>
</eConnect>
Hope this fixes your issue.
Regards,
SantoshG