Should I be worried?

I just finished work.

I agreed with my ex that I would pickup the kids (So our joint kid and my stepkid, which is why I'm doing this in my ex's time, otherwise my stepkid is missing out, I was his stepmom for 10 years and he is requesting to spend time with me as well as I like to spend time with him, I feel I should explain this for some reason.. and yes, his mom is aware that I still spend time with their kid and she approves) for a day to the beach one of these days.. I hadn't decided on a day yet.

Now I suggested to my ex this morning if I could pick them up tomorrow morning.

Now, I see that he still hasn't received my message, hours later.

So I called him, and his phone is off or he has no reception.

So I called my stepson because sometimes my ex's phone acts up, but his phone is off or has no reception either..

So now I'm kinda worried..

My ex is tight on money so I'm pretty sure he didn't have a lot of crazy plans, like going to caves or somewhere where he'd have no reception... so idk what to think and I'm really considering going over with my spare key to check up on them.

My ex has my baby (4yo) so my worry obviously extends to their safety.

UPDATE:

All is fine, they went swimming, my ex had actually told me that🤦‍♀️

There is no connection in the pool building.