When you first posted your ad, it was number one in your category, with maximum exposure to other users. As other people post however, your ad becomes number 2, 3, 4 etc. until it eventually slips off the first page resulting in less people seeing your ad.
Bumping up your ad means it will be number one once more with more users seeing it once again. You can bump your ad up by SMS as often as you like.
How do I bumpup my ad?
To bump your ad up, simply send an SMS text message to 87070 containing FREEADS and your ad id (E.g. "FREEADS 1234567"). Each SMS costs £1.50 plus your standard network rate. Please note, this is NOT a subscription service so you will only be billed once.