misremembering; false memory; memory lapse
Refers to remembering something incorrectly or having a mistaken recollection. Often used when someone realizes their memory was wrong.
That was my mistake in memory.
If my memory serves me right, he should have come here yesterday.
勘違い implies a misperception or misjudgment, often in the moment, whereas 記憶違い is about recalling past events incorrectly.
Compound of 記憶 (memory) and 違い (difference, mistake).