My oyster card has stopped working?

My oyster card will not scan anymore ever since ive come bk from holiday it scnaded onece can i fix it and how

• i had just come of the plane at heatrow used oyster card to come out to get picadilly line and it worked fine ie it scaned then it just stopped working. Have the metal detectors damged it or something but its been on a plane before and was fine. It is a freedom pass which my dad as a bus driver kindly gave to me ie its a bus operetor nominie pass which is hard to replace can i fix it my self if so how please help.

• Answer:

  have you passed thru any heavy duty metal detectors lately? (like the airport) they can magnetize your cards if you're not careful, i've had to replace some of mine before, for that reason. i don't think you can fix them once that happens, some people have said something about putting a thin plastic bag, like a grocery bag over the mag strip when sliding it and it seemed to work, temporary fix?