I have been working (present perfect continuous) VS I had been working (past perfect continuous)
Present perfect continuous
Present perfect continuous: is used to speak about an action that started in the past and is still on in the present. The action is not completed.
Example: I have been working at ABC for 5 years. (I started working 5 years ago, and I am still working currently)
Example: I am angry. I have been waiting for you for two hours. (from 2 pm-4 pm I have been waiting)
Example: It has been raining since last night. (last night, it started raining at 10 pm and it is still raining this morning)
Past perfect continuous
Past perfect continuous: to show that something started in the past and continued until another time in the past. The action is not on in the present.
Example: I had been working at ABC for 5 years. (I started working in 2009 and resigned in Dec’14. Now, I am not working at ABC company. So, we use the past perfect continuous)
Example: I was angry. I had been waiting for John for two hours. (yesterday, the action of waiting was on for 2 hours)
Example: The road was wet. It had been raining for many hours yesterday. (yesterday, the action of raining started and went on for a couple of hours and then stopped. It is not raining in the present)