TLC555: Simulation result different with calculation

Tool/software:

Hi team,

I need a simple circuit to generate a PWM of 1HZ, duty 50%, to drive electro-magnet.

I downlaoded Tina file on link https://www.ti.com/lit/tsc/slfm002, and modified R2/R3/C1.

but looks Simualtion and Calcuation are different, could you help review and advice, thanks.

TLC555 TINA-TI Astable Reference Design_modified.TSC