How to fix lose wire inside the speaker

ok I hope i am clear as i can. I have insignia speakers 2.1 that only use 38 watts i believe. the issue i have is my left speaker is not working right since i found out that the wire inside the left one is highly on lose as the sound goes on and off. I have no idea how to take apart. I do know a little how to fix the wire but its best to give me advice to fix lose wire.

heres the point help me how to take apart and give me advice about lose wire INSIDE the speaker