I 94 question

Hi, I went on a holiday to the US way back in 1992. I was there for just a month on a B1/B2 tourist visa. I haven't been back there since.

I think I may not have handed back the white card that was stapled to my passport on entry. Either it fell off or I removed it thinking it wasn't important. I just can't remember what I did with it if anything. Now I have learned that it is a record of your exit from the US.

I have since changed citizenship and am eligible for the Visa Waiver Program.

Will I be stopped as an overstayer if I return for a tourist visit now after 15 years?

Thanks