I loved my Shark robot while it worked!  Unfortunately, it stopped working about 2 weeks after my one year warranty ended.  The clean RED + “i” were flashing together -  the manual states that this "indicates that the suction motor has failed. To fix this error, remove any blockage and clean the filters. Check that there is no obstruction that would otherwise prevent suction."  When I contacted Shark customer service, they only offered for me to buy another Shark robot- no thank you!