Never. Science does not require belief only evidence, with it there is only what we as humans have learned and what if we survive will learn in the future.

I proud to be non-believer in my life

nope everything so far is either definable or in the hmm ok lets see category or...

I think I can literally say that in conversations with scores of atheists over the years I've heard one second-hand story about an atheist who converted. And it was not a re-conversion either, which fits my theory that lifelong atheists whose position is kind of a default rather than one that's fully considered and worked out, are far more vulnerable to it than deconverts.

It does of course happen. There's an atheist named Anthony Flew for example who in his dotage became a Deist. Fundamentalists love to crow about this, happily ignoring the fact that Flew did NOT convert to Christianity and as a philosopher of religion still held all sorts of beliefs about god that they would find ghastly. Frances Collins, an accomplished geneticist, DID convert to evangelical Christianity from his early academic life in which he described himself as an "obnoxious atheist". But his apologetic is standard-issue fundamentalist tropes that can convince no critical thinker. He is a living example of how someone can compartmentalize to the extent of affirming science in his field and being completely unscientific in his private beliefs.

If there was such a experience, it was decades ago when I was a child and (like worthless information, has been pruned from my memory.

nothing to describe. it hasn't happened. i have been an atheist for 51 years. i am not holding my breath.

g

Nope

My absence of understanding indicates nothing other that I do not yet have the necessary data.

I question things all the time. I probably, however, draw different conclusions than I might if I was a believer.

All my experiences cause me to confirm my belief.