Idea Cellular — Sim upgrade issues

I have gone through 4g sim upgrade procedure 2 times in the last two years. Still there are unresolved network issues for which customer care suggests me to upgrade my sim to 4g. As seen in the attached picture, there is 4g mentioned on the network symbol at the top of my screen which is the proof that my sim is already registered on 4g network. This is the worst experience with idea.