Problem with 4 wheel drive

Hello everyone I'm here helping a single mother of two with a 2008 toy 4runner when she put it in 4-wheel drive lo it beeps at her and will not stop in 4-hi no beeping can someone throw me a lifeline to solve this problem for this lady than you in advance

 

You must be stopped and in neutral to engage 4LO. 4LO is really only for low speed crawling, or if you're stuck.

 

I think its warning you that you are not in 4-Lo.

Neutral first as stated above.

 

Yes I know thank you I'm trying to find if the problems are in the transfer case if so what do I need to look for

 

But, does she know the above?? Maybe there is no problem.

 

So, it works in 4HI, but not 4LO?

Does 4 low engage and it keeps beeping?

Or, does it stay in 4HI or 2HI?