The cause of this behavior is media slippage during the load process. If slippage of the media such as the media on the core, or the core on the spindle occurs at just the right moment, the printer will silently cancel moving the carriage to find the media edges and instead will prompt the operator to input the media starting position and width.
To resolve this issue, carefully examine the current media roll and the media spindles. Ensure that the air core (for single-roll loads) or the dual-roll differential and inner hub are firmly gripping the media spool. Ensure that the media is attached to the core itself.
For additional assistance with the dual roll kit, refer the Dual Roll Kit User's Guide, chapter 3.