iomega hard drive not mounting

Hi I have a Iomega ultra max external hard drive that will not mount. It started to play up about a week ago

( I have had it for about 2 years) kept getting a message to say I had'nt ejected it properly, while it would still mount I checked it was working OK through disk utility and that said everything appeared to be working OK , but now it will not mount at all and when I power up the external drive I just get 2 red lights flashing alternatley. Any help would be useful. Thankyou.