So odd. New slide not striking on first pull

Got a new compact today and brought the full size for fun. The green slide was on the full size, and it would not strike on the first pull. I swapped slides, green on compact frame, and put over 100 rounds through with no issues.

I tried again several times and it failed. Once I racked to eject the first round, I emptied two mags with no issues. The full size had no issues wirh the Leo slide.

I initially thought firing pin, but it shoot flawlessly on the compact frame. Any ideas?