2008 Optra/Lacetti P0342 Pending Code: What Does It Mean and How to Fix It?

Hi everyone, I hope you're all doing well. I'm a bit confused about the difference between 'Stored' and 'Pending' OBD-II diagnostic codes. I own a 2008 Optra/Lacetti with a 1.6L engine. About a month ago, my MIL (Malfunction Indicator Lamp) lit up showing a P0342 code related to the camshaft position sensor. I replaced the camshaft position sensor, but the issue has not resolved — the MIL did not turn off. When I used the MD802 diagnostic tool to check the vehicle, I found that the P0342 code reappeared as a 'Pending' code. After clearing the code with the scanner, it returned again within two days, this time without triggering the MIL and still listed as a pending code. This behavior is very confusing — what does 'pending' actually mean? Is it just a temporary warning or could there be an underlying issue? Could anyone please explain the difference between stored and pending codes and help me understand why this code keeps reappearing in pending status after clearing? Thanks in advance for your insights and advice.