@NicoleLargey are you sure that you are not having a new fibre connection fitted soon? The cable you have is required to connect to t nhe new ONT unit the engineer will fit.
if you are certain you will be using partial fibre you can buy a simple DSL cable with rj11 connectors which are available on line or in most any hardware store. Howevervits pretty unusual for Skybto have sent out the wrong cables
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
