That happens to me a lot.
Many times I couldn't remember how to spell "until"
I just couldn't remember if it's one L, or 2. I knew at one point how to spell it, but somewhere along the line, I question myself because it seem kinda lacking without two L(s).... just looks funny with only one.
And since it first started, it continued for a few months before I finally got it embedded in my head again.
It took that long because everytime I tried to remember what's the correct way to spell it, I remember the back and forth arguments in my head about whether it was one L or two. So it constantly created doubt in my mind.
But now I got it... at least, I think I do.
*chants to self*
One L...
1 comes before 2 ...
1 comes before 2, first comes, first serves...
One L.... One L...
one before two....one before two, one before two...
One L still looks funny as hell...
oh sh!t, I've done it again...
And here comes the doubt...here comes the doubt..
Which one is it.... one L or two, one L or two...one L or two