Light bulb flicking

I bought the normal round light bulb on the 5th of May 2025 . Yesterday in the 11th June 2025 the light is flicking and switching off, I called to complain and to tell them know that I lost my receipt. The lady said it's fine I should go to the store and tell them to replace the light. But in reality that will never work out, they will take me from pillar to post because Firstly they don't know her. I told her that maybe she must write an email to them and se said she doesn't have any connection with the store. So how will I go there while she doesn't have any connect with the store and clearly they don't know her so how will they believe me