My tare knob is no longer working.
First, make sure that your platform (plate or bowl) is on the mount when taring. This sometimes gives the gears inside a start with making contact with each other with weight on it. If this method does not work; your scale may be damaged internally and will need it to be inspected or replaced.
The face cover has fallen off.
You can simply pop the front cover back on.
Valid for Mercado Stainless Steel Dial Scales. Model #: DS132P (plate), DS115P (plate), DS115B (bowl), DS63P (plate), DS63B (bowl), DS21P (plate), DS21B (bowl)