@Jamie-Childs ,
I hope all is well. There are several things that could be causing the behavior. Let me ask you a few questions, and let's see where we get to....
First, is this the only machine out of the entire SCCM system that is having this issue? If not, only one in a particular Collection?
Second, are you using Boundary Groups?
Third, is this "new" behavior? if no, when did it start? what was the last major update/change that was made prior to the behavior starting? If yes, ... same ?
Fourth, when was this machine deployed/imaged? is it a new or old machine? have you checked the SCCM client agent version? is it the same as all the other machines that are working normally?
Fifth, have you examined any logs on the client to see what may be happening? ( a reference for ALL log files can be found here in case you need to figure out which one(s) to examine and where they live ) https://docs.microsoft.com/en-us/mem/configmgr/core/plan-design/hierarchy/log-files
Start with pondering and answering the questions if you can, and then we can see where they may take us...
Cheers,
Adam