I bought a Batboostor a long time ago. I was very happy with it, except that these last days, it no longer seems to work.

Maybe I made a mistake in using it. I don't know.

In all cases, when I plug it into the mains with or without batteries to charge, the red LED and the green LED flash alternately.
I tried to contact the company but it seems to have been liquidated in 2015!?! It is also surprising that a company with a promising product like this one goes bankrupt.
So I don't really know the reason for the malfunction.
Could someone explain this to me?
Did you encounter the same problem and did you solve it?
Kind regards.