Series 7 passcode bug?

Hi,

After upgrading a series 7 45mm watch I'm seeing (intermittently) that tapping the passcode to unlock the watch sometimes doesn't work because one or more numbers do not register after tapping them. Let's say the passcode is 123456. You tap 123 and you see (briefly) three dots representing the three digits, but the 3rd dot disappears quickly. The workaround is to re-type the '3', but you have to notice this has happened. I suppose another workaround is to unlock using my phone (which I'll setup), but I was just wondering if anyone else is seeing this. Again, it happens only intermittently (so far, about 4 times out of 20 or so). Would appreciate if someone else could confirm they've experienced this too.