My twitter app doesn't have access to photos and videos. how to fix this problem?

I don't use any twitter apps so I can't check, but it might be in Settings > Privacy > Photos

If you want an App to use your existing photos on your iPad, but you do not see it requestin gaccess to your photos under the regular privacy setting then...you have to go under Settings, Restriction, then under Privacy click on Photos and you must Allow Changes. Then next time you try to send a picture from Twitter or Facebook it will ask you if you will allow the app access to your photos. Accept.