vin168888,
Firstly to the best of my knowledge these players do not come in 8GB, I have not even seen proof they come in 4GB. So your chip could well be a dude.
But I investigated the number you have given as follows. It looks like your chip is a HYNIX brand judging by the HY prefix. But looking at the rest of the serial number Hynix does not make a chip by this number. If it were a Hynix 8GB chip it's serial number would be HY27UH088G2M or HY27UG088G5M If you look at this product code sheet from Hynix
HERE most of the number you quote does not exist or is wrong, which leads me to believe your chip may be a fake.
You also mention your player was restarting, this is also a symptom of a fake chip.
Having formatted the chip and found it's capacity has gone from 8GB to 46MB is also another sign of a fake chip.
What can you do about it? I have yet to hear of anyone recovering lost memory. As I suspect your chip may be a fake I suggest you contact your supplier and demand a refund in full. If he is a crook you will proberbly get no responce.
As you do not have a firmware backup your only chance of getting it going again is to just keep following the recovery guide and trying different firmware till you find one that works.