I Can't Join My Friend's Server

We were playing together in my friend's server 2 days ago. But my all servers has been deleted. And I added that server again but now I can't join server (since yesterday). It just says "Server Not Found". But my friend can join. Moreover when I open another server, we can play together. How can I solve this?

I can join "Minecraft Server12" named aternos server (It's my server). But I can't join other aternos server. I took this screenshot when both of servers online.

Quote from Roman

Please check the IP entered in your server list, it has probably a typo or is wrong.

I checked it word by word. But I can't join...

Quote from Roman

What is the server ip?

It's dingillerilesurvival.aternos.me (Version is 1.14 vanilla) but he can't open the server now, maybe he can open 3-4 hours later.

Quote from Mc88Donalds|Julian

that ip doesnt seem to exist

Yes but I'm sure that it exists. I was playing in that server but now I can't. Just my friend can play in the server.