For some reason, Dolphin suddenly decided it would group my Downloads directory by date - like Windows. I very much dislike this, and i don’t know why it was suddenly implemented on my potato. I didn’t turn it on.
I removed grouping: Menu > More > Viiew > Show in Groups.
Apologies to Dedoimedo for pinching his picture:
It took me a bit of DuckDuckGo’ing to find that because what i had found was “View → Group”. Because the View menu is in More, i overlooked it. I instead went into Configure > View and couldn’t find it.