lose count (of something)
To fail to remember or keep an accurate talley of how many of something there is, often due to there being a great amount. At this point, I've lost count of the number of times they've yelled at me! Ah, shoot—I lost count! I'll have to start the whole inventory over again now.
lose count of someone or something
to fail to be able to count someone or something, especially because there are so many. I have lost count of the people who have asked that question. I am afraid I have lost count of all the times we have run out of money.
lose ˈcount (of something)
not know how many there are of something: He’s had so many different jobs that I’ve lost count (of them all).