19" hansol 920p monitor
To my knowledge, it is not the zoom that has to be adjusted but rather the horizontal width, zoom would expand all (to, bottom & both sides) whereas your only concern are the two sides.
Should the horizontal width not fully expand, then there is an internal problem with the horizontal deflection circuitry which could either be the yoke, a capacitor or shunt diodes. In certain instances, a below normal voltage at the mains or the internal power supply could also cause this.
Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information.
Good luck and kind regards.
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