Good to get you as I had a problem getting started. Somewhat you asked. 3 Red flashes no green crash just stays green.
Sorry 3 red flashes no green flashes
Ok strange as it should have given green flashes as the red is just half the error code.
As to the fault have you remvoed the condenser chamber at the bottom and check that isnt blocked up?
Remove it and clean it out using a hose pipe if you can and give it a blast through as if this is blocked up then this can cause problems as well.
Then if you can remove the top of the dryer and look down the front on the inside and there at the top of the drum is a carbon stick touching the drum.
Use a damp cloth and give the drum a wipe were the carbon brush runs and clean that as this is what senses the moistor in there as the 3 flashes is a drum sensor fault so clean that and see what happens from there and let me know.