Hello, we have Whirlpool Washer model LSN1000HQ0. The upper agitator (the long tower like)has stopped working (does not agitate at all)but the bottom one works. My guess is it has some how separated from where it is supposed to agitate. Can anyone please tell us what can be wrong ? We are seniors and do not want to call the repair people as they are expensive, so we want to try and fix it ourselves, if we can.