Incorrectly flagged for HSA excess contribution

On the "Let's enter your HSA contributions", I correctly note the separate employer/payroll contributions ($2150, which was extracted from my W2) and my personal/post tax contributions ($2150) that sum to the 2025 max HSA contribution of $4300.

When I click "Calculate max contribution limit" on one of the pages in this flow it confirms "Your maximum contributions is $4,300".

But when I get to the final page of the HSA flow, it states I have excess contribution of $2,150. Only when I remove my personal contribution amount does this excess contribution notification go away.

What am I doing wrong?