Cobra Insurance?

My dad got insurance through his new job using cobra. I believe it’s dental/vision/health. The new insurance is blue cross blue shield and that’s the same company as our old insurance. The app shows the plans as inactive still and we can’t figure out what our new policy number/member id number is and I can’t find any answers on Google other than it states “Since COBRA insurance is a continuation of your previous employer’s group health policy, you will be able to use the same ID cards.” Is this accurate? I don’t know how to confirm it and my sisters dentist and her doctor too (she lives away from us) wasn’t able to find anything even when using our dads social. Could it be that enough time hasn’t passed for it to be fully active or is the policy number actually different? We’ve been signed up for less than two weeks.

Ps, please no negative comments. I’m young and still on my dad’s insurance so of course I’m ignorant when it comes to knowing how insurance works and how long it can take for it to become active.

Thank you in advance. Any information is helpful.