My old W995 lay down and died after 11 years, I couldn't find a modern dumbphone with anywhere near the specs in certain areas so I opted for a used one off E-bay, it came in great condition but it seems to be t-mobile branded (or maybe has old firmware, I can't see the version number) Unfortunately it doesn't support conversations in texts so all you have is an Inbox and Sent folder to trawl through which is a pain so I was hoping to de-brand or upgrade firmware, whichever is needed to get this feature back.

My old phone under firmware version says:


I found a file in the download section titled W995_R1FA035_MAIN_GENERIC_HI_RED53 but I'm not sure what to do next having never worked with phones much, could someone talk me through what is needed please?