My indicators and hazards have stopped working?

I had this problem with my ford ka 56 plate and the relay switch got changed as they said this was the problem but 4 weeks later they have stopped working again. They don't come on at all. Any ideas what could be causing it as surely it can't be the switch again as its just been changed

You might wanna begin tracing wires from the relay panel where that relay is plugged in, to see if you can find a wire with a bare or melted spot on it which will cause a short.A short will burn the relay up.A relay is the same thing as a fuse but it allows higher current to pass through it that would blow a normal fuse up plus it also acts as a switch too. The short could be present in a wire between the turn signal/hazard light fuse and relay or between the relay and actual bulbs for the signal lights. If you turn the flashers on and notice that one particular bulb is dimmer than the other three, the short is probably between that bulbs socket and the relay.So if the front drivers side, rear drivers side, and front passenger side blinks bright but the rear passenger side blinks dim, that's the suspect bulb wiring to check. Check your fuse panel too for a turn signal/hazard light fuse that's blown and make sure you don't have a flasher fuse installed. Your turn signal switch needs checked too

Could be a few things. Take it back to the place that sorted it first time, tell them it has stopped working and get them to look at it again. Their work must be fit for purpose, so it shouldn't cost you a thing. Threaten them with trading standards if you have to.