Question HDD extern Seagate Expansion + 3TB, 3.5", USB 3.0 problem

Aug 3, 2019
I have an external HDD Seagate Expansion + 3TB, 3.5", USB 3.0 for some time now (2 years or more) and never had a problem with it until now - if it can be called a problem.
Since it is a 3.5" it has separate power supply and I always kept the USB to pc connected and disconnect the power of the HDD every time it was not used. It has a blue light on the case which is on only when power is connected and HDD is working (and off when power is disconnected) until tonight.
Now when I pull the power out of the HDD the blue light goes dim and flickers but does not go off. It is like the HDD keeps receiving a small charge by USB but not enough to make it work.
Is this a problem I should worry about?

For now I pulled the USB out of the HDD - on the HDD end since on pc is connected on the back (but that is not ideal since the cable has a weird connector on this end that is a bit hard to put back in)