A large, mature jasmine vine like yours probably has its roots out under the lawn. Have you maybe changed how you are caring for your lawn lately? A lawn service spraying weed killer on the grass could be causing this kind of peripheral damage.
How about the water you're using? Any changes lately such as maybe you started using well water instead of tap water? My well water is much more alkaline than my tap water.
What is behind that wall that the vine is climbing? Could someone be spraying or cleaning or painting on the other side?
