Charging issue The tablet powers on and everything is fine only if the power cord is plugged into it. As soon as I unplug the charger the tablet shut down. The battery is getting no charge at all.....

Not familiar with your device but I think it may be a bad charger cord, wrong cord(my phone displays "wrong charger" when I grab the wrong cord), or the charger port on the device could be bad. If it's been charged before, and now refuses the charge it could be a bad battery.
Sometimes, if you check the home site(computer), the company may have posted some help info. I know Amazon does for their Kindles.

Allow the charger to charge the battery with the tablet OFF over night. The tablet requires MORE power than the charger can provide - but the charger provides enough power to slow charge the battery. In the morning it should be fine - unless the battery no longer can support a charge.

Please make sure the tablet is charged for at least 4-6 hours. Also, make sure the correct button is being used, oftentimes we hear the back or home button has been used in error. If the issue persists, you can try performing a power reset. There should a power reset button near the charging port. It looks like a tiny hole. While plugged into the charger, use a paperclip to push the button inside this hole for 3-5 seconds. If it turns on, please allow it to charge for 4-6 hours before using it. If you leave it on the charger for longer than the allocated time, you will go back to having the same problem as before. If the power does not come on, please leave it plugged up for 4-6 hours then disconnect it from the power and turn it on.

If your tablet does not have the reset button: With the tablet plugged into the charger, hold the power button for 10 seconds then click the volume up once. If it turns on, please allow it to charge for 4-6 hours before using it. If you leave it on the charger for longer than the allocated time, you will go back to having the same problem as before. If the power does not come on, please leave it plugged up for 4-6 hours then disconnect it from the power and turn it on.
Support Troubleshooting Guide

It could be the battery is already on its end of life. Could be, your charger can't deliver enough power to work and charge the tablet. Before you start worrying, please leave the tablet on a charger over night, with everything switched off. Then remove it from the charger and start it. If you keep having the same problem, and you can't check the quality of the battery, start saving for a new tablet. Not worth paying 100 dollar for replacing the battery, if you can buy a new tablet for the same price. If you can open the tablet, check if the battery is still connected correct.

Sounds like it does not have enough battery power to stay on. If you have not tried to charge it, you should try that first. If you have, it sounds like it is not getting charged or not holding a charge. Could be bad AC power source, bad charger, bad charger connection or bad battery. Take steps to confirm that each of these are good. If all of these are good, sometimes the tablet can become so discharged that it will not allow itself to charge. When they are in that state, sometimes you can trick them into charging again by repeatedly disconnecting and reconnecting the charger as follows: With charger plugged in to AC power source, connect the charger to the tablet. Pay attention to the screen or LED or whatever indicator your tablet has to let you know it is charging. You may see it momentarily indicate charging, or maybe not at all. Then unplug the charger from the tablet then immediately plug it back in and pay attention for the charge indication again. You may have to do this a bunch of times (like 20) until you see the indication that it is charging. When you do get the indication, stop unplugging and re-plugging and let the tablet charge for 24 hours (to a full charge). This trick doesn't always work. Sometimes the battery or charging circuit or an internal connection is bad and no amount of unplugging/re-plugging will fix a hardware problem.

I suppose this is some cheap android tablet. If the power button does not turn the tablet on, try plugging in different chargers and cables. Perhaps the battery is not charged. If the tablet has been dead for awhile it might take awhile to charge the device up enough to turn the screen on. So, try cleaning the charge connector with some alcohol and check it for damage and allow port to dry before plugging in any power. Just experiment by moving the power cord around and perhaps the connector is loose pr something. I suggest leaving the cord plugged in even for days or hours because it can take different devices a long time to charge if they are flat.

I tried numerous attempts to fix this problem, including a re-format of the tablet. In the end, I had to trash it. The cord was tested and was fine, the plug was fine, it must be something in the power mechanism of the tablet that failed.

pull the battery out and unplug the power changer hold the enter key for one full minute then install battery see what charge amount says if half way drain it till compter shuts off then charge, if it does not fix the problem the battery is dead.Rate if this was helpful.