Hi all... Similarly to previous post by SophC, I'm on my fourth Minimed 640G pump. On January 3rd 2019 I ended up in A&E with DKA after my pump failed. There was an insulin flow block but my pump didn't alarm. Medtronic replaced the pump & within a few days, the pump was alarming that there was an "Insulin flow block" 2 to 4 times per day. Each time, I did a full set change. I've had three replacement pumps. I tried using different cannulas- I prefer the Mio but tried using the Sure-T with the same error occurring; I used cannulas from 4 different boxes (with different lot numbers), I tried using different reservoirs & moved the sites all over my body but I continue to get the "Insulin Flow Block" errors. I'm currently on pump #4 & sure enough, when I bolused for my dinner I got the dreaded "Insulin Flow Block" alarm. I don't trust my pump. I feel like I'm going crazy. Is anyone else having a similar problem???