Unlimited Telco Plan oh Unlimited Telco Plan

Recently I just changed my Redone plan RM 8 to DIGI NEXT RM 15 plan.

This DIGI coverage really jialat, my house is no service at computer room. Only Living rrom have 2 bar.

I have complained multiple time but still the same.

Why the coverage so Poor???

Should I change again? I am thinking of U Mobile U25, any suggestions?