I am wondering a few things. Hiow long have you had your piggy in this cage, and how long have you been trying to encourage her back down the ramp? What is your present ramp made from, what is it lined with, does it have sides and how steep is it? Do you have a picture of it?
To make your ramp feel more secure for your piggy, I suggest (like others) ensuring the sides are high, and the slope is slight. Make sure it is steady, and there is no movement when she walks on it. Have you tried the trail of veggies trick? You could always try making it into a tunnel - using cardboard over the top, as a temporary tempter! Perhaps moving it to one side of the cage would help steady it/make your piggy feel more secure? If she is upstairs, have you tried putting her veggies downstairs so she is tempted to come down?
Whilst my pigs all love their ramp, i hear of some pigs who never get the hang of it. It is well worth persevering though - keep trying! (and maybe a friend pig would help her feel braver too!
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