There are better pickups than the copper Realist for the same position. Think about a Shadow SH-965NFX or an APTflex.
Seems like the Lifeline has a problem. Probably a contact failure somewhere. If you are lucky it is only inside the plug (I hope you can open it and look for a short or a disconnected cable). If not you might be able to open the part at the pickup where the cable is connected and check the cable for a contact break and if you find one replace the cable. (Be very quick when soldering, piezos don't like heat!) But if you just purchased it, try it a last time on a different bass with one-piece adjusters and if it doesn't work there too, send it back as a dead on arrival item.
Seems like the Lifeline has a problem. Probably a contact failure somewhere. If you are lucky it is only inside the plug (I hope you can open it and look for a short or a disconnected cable). If not you might be able to open the part at the pickup where the cable is connected and check the cable for a contact break and if you find one replace the cable. (Be very quick when soldering, piezos don't like heat!) But if you just purchased it, try it a last time on a different bass with one-piece adjusters and if it doesn't work there too, send it back as a dead on arrival item.