The dr didn't say what might have changed?
No new imaging to check?
Just wondering ...
maybe the DDD has progressed
the spacers moved
something new?

Might be time for second opinion from independent dr.
I would ask for new imaging, if your dr can't communicate why the pain started up suddenly..
Either it is not treatable and long term pain management needs to be talked about.. but the dr needs to be clear if that is the case...( maybe a spinal stim implant) , or beyond drs skill set, or ??

You might need to press for the hard truth, or for new imaging...and ask for a copy of the written MRI report if you get one.. It helps when going for other options too