Getting UOM conversion error while creating Purchase order with Receiving location preference

I have set up receiving location preference for particular order type and line type. In the definition, I have defined Volume UOM as LT for both shipment and Item.

In Branch plant constants for this branch plant Volume UOM is set to CI.

For all items the volume UOM is LT and accordingly Volume is defined in UOM conversion P41002.

However when I creating that particular Purchase order, I am getting error UOM Conversion CI to LT Unsuccessful. Even though in order the value of volume uom is populated as LT.

If I define the conversion between CI and LT in P41003, then preference works fine.