Why won't my Nokia 735 charge with the back cover on?

[Windows Central Question]

my nokia 735 wont charge with the back cover on

my nokia 735 wont charge with the back cover on, I take the back cover off and it charges no problem, also I can turn the phone off and on with the back cover off, as soon as I put the back cover on I can turn it off but not back on, I have not put a sim card in it as yet as it is a Christmas present, is this a fault???? any help would be appreciated