LG D858HK unable to get into download mode suddenly(not brick)

I wanted to flash the 20e kdz to my phone as 30a sucks. So I tried to boot my phone into download mode by pressing the vol - and plug it into the PC but it didn't work, I displayed the LG boot screen and show me the battery status. I am sure that the buttons on my phone is working well and it's not my first time to flash it. Can someone help me with this?

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