I have a stamped B2 in my passport but only applied for an ESTA

[Van_go]

I've been to the U.S. multiple times on my ESTA, however, when I flew into Houston earlier this year the officer stamped me with a B2 that lasts 6 months, even though I don't have an official B2 visa in my passport.

I went on to Canada afterwards as a tourist, and then was approved for a work holiday visa there (I'm Australian) and so needing to do a visa run at the U.S. border to recieve my work visa, the U.S. official stamped my visa again with the ESTA, that lasts only 3 months. He didn't say anything about my B2 stamp though. I was confused as to what this meant.

Fast forward to today, and after crossing the borders multiple times without any extra stamps or concern from the officers. This time I came back into the U.S. on the day of my ESTA stamp expiring, I asked if the officer was going to stamp me in again but he said it's valid for another 2 months (the B2).

My question is will I be considered overstaying now? Or was that last officer correct? It makes sense that if someone stamped me with that originally that it should be valid. But I'm worried that if I try and leave, that another officer might see that as me overstaying. It's stessing me out, does anyone have any info on this happening before? Should I call and ask an agency about this?

[immihelp]

If you entered the US on ESTA, you should not stay for more than 90 days. Otherwise, you will still be held responsible for overstaying, even though it was officer's mistake.