I'm feeling very silly and incompetent today. Please reassure me I'm not the only one who makes mistakes like this...
I'm 37. Own a house, professional job, 2 kids, generally very boring sort of life. Normally always on top of bills, insurance, life admin etc. Yesterday morning I went downstairs to find water pouring through my kitchen light fittings - a toilet on the floor above had sprung a leak overnight and there was (thankfully clean) water everywhere. DH standing there going "Oh my God what do we do?"
I called a plumber, found and turned off the main stopcock and started cleaning up while DH sorted out the kids. Fortunately the plumber was able to come quickly and sort it, and it doesn't seem like any of our possessions have been seriously damaged, but we will likely need a new ceiling in the kitchen.
Here's the problem - I thought our home insurance was set to auto-renew (I know, not the most financially efficient but at least a useful safeguard). Turns out, it wasn't. In fact, it expired in 2019. For weird historical reasons we have separate buildings and contents insurance, the contents is still valid (but not needed) but no buildings insurance. It seems that in my 3 month old baby haze back then, I misread "will not renew automatically," and forgot about it ever since. Thank goodness we didn't have a fire or anything! 
So, expensive mistake to make. Anyone else able to make me feel less alone by telling me when you dropped the ball on adulting?