Htc one m8 battrey problem or something else?

[AC Question]

I've recently had my phone fixed as the lcd sreen was cracked. After a month later it turns off when i'm not using. To specific say for example when i leave my phone to go take a number 2 i'll come back to see it fully turn off. Also when i put the alarm on, the next day it doesn't set off because the bloody phone turns off!. I think it may be due to the battrey becuase ill charge the phone say at 60% and when it turns off and i turn it back on it'll jump down to 39. I even tried re-calibrating it and putting it to 100%. Nothing. Its weird how it turns of WHEN I'M NOT USING IT

 

[belodion]

You may need a new battery, or it may be a poor connection.

 

[Almeuit]

You may need a new battery, or it may be a poor connection.

I would say this -- The repair may have not been done properly.