I've made that mistake before by adding an extra '0' on bet365 although, in my defense, it was 3 in the morning and I was half awake.
The worst was the time I made a big bet on a Club America total (think they were playing Queretaro) and I watched them hit the goal post and crossbar 5 times in the 1H to go scoreless. I got so mad, I unloaded my entire account on the 1.5 live total at HT without even thinking. Thankfully it finished 3-0, LOL.