Engine starting problem

Hello,

Slow starting issue can be due to few different reasons.
Does it happen every time you try to start it? Or only when it's cold or in the morning?

If the battery and starter checks to be good, then it could be due to the engine not getting proper amount of fuel at startup. That's why it just cranks and cranks before starting.
Checking the fuel pressure can help with the diagnostics.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

If the issue due to an engine sensor, it could trigger the check engine light. Is your check engine light illuminated? If so, getting it scanned and retrieving the codes will be the next step.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Please let me know little bit more information.

Thank you.