Can you supply a schematic? 555's are pretty mundane tech, problly a wireing prob.
This is a debounce that is decoupled to not retrigger until the switch is opened.
You can change either the resistor or the capacitor. But the resistor needs to be at least 100k to make it much greater than the 10k. Otherwise the timing will be assymetrical.
Be sure to connect all unused inputs of the IC to gnd.