The clutch reservoir got low & now I cant get pedal back as it was. Help

How on earth did you check the slave cylinder for leaks? It's located inside the bell housing of the transmission on the input shaft. These slave cylinders, by the way, are beyond notorious for multiple, continual, repetitive failure. Not at all a great design...and they used it for many years. I can tell you from personal experience that I went through at least 3 in 4 years. Even the "revised design" from new parts that added different seals did not help. All that to say: Suspect faulty slave cylinder. I'd bet on it.