Airtel — harassment regarding sim activation

With due respect to the india's one of the best network airtel, i am being forced to write this letter with great disappointment and after handling so much harrassment.
Myself soumik bhattacharya, fashion photographer n independent film maker, working in mumbai now.
From last few years i have migrated to airtel. My mobile number is[protected]. It's my oldest & used as primary no. Everywhere.

On 6th september, i had converted my post paid connection to prepaid in kolkata and i was given a new sim by the outlet. After 2hrs the sim showed tower strength n all hence i broke the last postpaid sim. As u had my flight to mumbai on same night, i didn't got the time to verify it by dialing 59059. From 7th september onwards i have in great harrassment. Neither i am being able to call 59059 nor 121.
Customer support of mumbai circle is telling me to contact kolkata and vice versa.
I even did sim swap here which mumbai outlet suggested. They provide me a usim. But still it was of no use. After several days again my dad went to airtel outlet of howrah and they again gave new sim and made it activated. Today i received the sim by post. Now the biggest irony is, after putting it to my phone it's saying invalid sim. Now the customer support of kolkata is saying i need again a new sim.

Now here is my question. Do you think it's a kind of a joke or something? I am a professional guy registered under trade union act 1926, as a fellow member of swa, assistant director of iftda.
[protected] is my official no. Which is used in everywhere like calling purpose, social media platform, net banking etc etc.
Do you have any sort of idea what kinda harrassment i am bearing? Being a faithful customer of airtel for so long do you think it was kind of expected act from you people?

I want to resolve this matter as early as possible and want to lodge a complain in consumer forum and as well as for compensation