Electrical

The first symptom was the engine rpms kept going up and down instead of an even idle. The second was that the battery died and was not being charged. The third is that none of the gauges in the dash are working and the battery light is on. This is still happening even though the alternator has be replaced and the battery was charged at an auto shop. We've checked the fuses and none appear to be bad and now don't have a clue as to what to check next or replace if necessary. Thank you in advance for you assistance and timely response.