Telegram Version to download for Mac OS X El Capitan (10.11.6)?

I had telegram downloaded on my desktop, and tried to upgrade it this evening. The older version that I had was then replaced by a version which does not work.

Does anyone know of a Telegram version that I could download for this computer?

No, I don't have Time Machine hooked up. And I don't know how to get back the old version of Telegram that was replaced by this bonk version.

I have a mid2009 Macbook pro. It is old and out of date, and I don't know if I can even update the operating system, which is incompatible for many Apps.