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Hi Adam12397 and welcome to the Sony Users Community.
One explanation could be that the battery is completely dead. I presume you have cleaned the battery contacts. The only way to find out, is to borrow a working battery from a friend or a Sony Shop and see if the problem exists with a battery known to be working.
There are other possibilities. The Power Board may have failed or another electrical connection problem that will need someone to check inside but I would try to get hold of a replacement battery first.