Is a Modification Legally in Effect W/O My Signature

My question involves child support in the State of: Pennsylvania

A modification to my child support was ordered to an amount I am really struggling to pay. I have already appealed it, however, if my signature is not on the new order as it should be, is it fully legal and am I obligated to pay that new amount?

Of course. Your agreement/signature is never required.

The court can absolutely order a new amount.