Hello advice needed please

we have stickup cams (now called outdoor) 2 are wired and 1 is battery. Now we've moved the battery one but.... as its in such a busy area the battery is going flat in a day! so we thought solar would be ideal. Ive followed the instructions, but I cannot get the solar to connect, its driving me nuts. has anyone actually managed to connect to solar, or do i need to replace the cam and start again. Thanks