I allowed my battery to run down and now it will not charge. The Oled shows either 0% or 1% alternately but never moves on.
Quick check. I had a similar issue. Check that, when the charger is plugged in, the red LED next to the power switch is lit. Mine was intermittent. It went red as I plugged it in then went out.
If it is not lit, gently, slowly, and slightly wiggle the plug to see if it blinks or comes on steady. Violent movements might damage the internal connector so don’t force it.
I found that If I let the cable hang when plugged in, I could charge the battery till I got a replacement. All good for months now with new charger.
That did not help me. The red light only comes on for a short time and the changes to pulsating green. The red led on the other side is lit and the green shows access to the SD card. playing with the charging cable had no effect. I wonder if the battery needs replacement. How do I get instructions for that?
Register your product if you have not already done so then use this link to place a Support Request. Note that you may need to scroll down a way to get to the request message. Copy the URL and past it into your browser.
I entered a support request and received a couple of questions from Riz. I replied that I had a standard pi-top  and a robotics kit and provided evidence that I had bought and registered them. I have heard nothing since then.