Replaced my screen and charging symbol comes on but doesnt want to turn on help?

[joedirt176]

My htc m8 screen cracked so i decided to replace it and i bought on on ebay (mobiescreen) which was identical to mine, after replacing the screen and following all the steps correctly i put it back together but the screen doesn't turn on unless i put it on charge the charging symbol on the screen appears but i cant power it on. I have tried to reboot it. I know the screen works because it clearly shows the charging symbol but doesn't show the percent of battery. Thanks for your time