Call of Duty Modern Warfare Unable to Download PS4?

Have the following problem: When I try to download Cod Modern Warfare, I always get the error message after a short time: DNS server can't be used. (Image added) That means the download starts briefly and then breaks off. What can that be?
Use my cell phone with LTE speed as a Wi-Fi connection. Could it be because of that? But I've already downloaded various other games like this.
I already tried to set the primary and secondary DNS to 8.8.8.8, that didn't change anything.
My download speed is 20 Mbits. It says that the download should take a total of 9 hours.

With best regards,

Do you know what your primary and secondary DNS settings are? If so, switch this to 8.8.8.8. That should fix the problem. If you don't know how to do it, I can explain it to you step by step.

I've already done that, I'm not sure if everything was correct, it would be really nice if you explained it again