RPI not handling external hard drive

Hello guys, first of all, thanks for the awesome project and for the support.

I'm getting some trouble on my rPi with an external hard drive. It happens that even using an external power source for the hard drive (the knup one on the attachments, that exclusively feeds the hdd), it still shows the bolt icon at the top right corner and randomly shutts down (or unmounts the hdd). What i dont understand is why it is happening. Even with stronger power sources on rpi(the attach shows a 5V 0,7A, but i've also tested with a 5V 3A), the same issue occurs.

Libre elec version running is the latest.

Thanks.

Good. I've tried another shitty (but better) power adapter and it seems to be working pretty well...Even the red led over the rpi has stopped blinking. Even though, the bolt icon remains at the screen (but this time without any sort of stuttering or sudden death of the system).

Quote from Klojum

Also "latest" is not a version number

Sorry, tried my best to make a consistent topic adding images and relevant info. Anyway, thanks for the reprehension