The 4 led on battery are Blinking 10 time, Impossible to charge

I received the bike for free but i have some issue :

· Battery won't charge anymore, The charger light stay green.

· monitor won't start

· Battery led blink 10 times only when i pushed the button when the charger is plugged.

· I tried the trick by reversing the front wheel, but the charger light still stay green

Then

· I've managed to dismount the battery and charge it to a benchtop power supply at the maximum it can do : 30v and 1.5a ( limits of the benchtop )

· Battery giving me 19v before charging (Black & white wire ) and 21v (black and Red wire)

Results

Still impossible to charge the battery ( voltage is too low i think ) but i'll try again to reverse the front wheel with an Electric drill.

Actually there is still all the led blinking 10 times when and without Charger this time.

Do you think there is any hope to revive the bloc? There is any chance that the BMS is broken due to a direct charge ?

Maybe should i charge each battery individually ?