Hi guys, my phone line had a fault repaired today but the engineer didn't reset the DLM. Stuck at 7mbps vs my usual 21mbps 
My ISP has said I have to wait for DLM to increase it, but some random dude has messaged me asking for my "CLI (Landline Number)" and they'll issue a reset for me..
Is this a scam or anything? What could someone do with my home phone number? Are they actually able to reset it remotely, I thought an engineer would have to be called out to do it?

My ISP has said I have to wait for DLM to increase it, but some random dude has messaged me asking for my "CLI (Landline Number)" and they'll issue a reset for me..
Is this a scam or anything? What could someone do with my home phone number? Are they actually able to reset it remotely, I thought an engineer would have to be called out to do it?