English being what it is, is this DNS server yours or just one you are using.
If you are having DNS issues, why not change to other DNS (servers)?
This is not something most can troubleshoot. Troubleshooting a DNS requires access to the DNS control panel and this is why we must be absolutely clear if it's your DNS or just one the ISP assigned you.
There are so many articles about changing to another DNS that that is not a hurdle. But you wrote about your DNS and troubleshooting so it may be a rare setup so let's hear what DNS Server you deployed.
My DNS server disconnects 10 to 12 times a day making using the computer a pain. I do not know what to do - HP no is help and want to charge for help,. Verizon gave me a new router but it is worse since then so I do not think that is it - do not know who to call or how to troubleshoot but very frustrating. Also, have another question - I got Playon years ago when CNet first suggested it f(cost way down now) but it appears when it records videos for Playon they are also backed up on Chrome, Google, OneDrive and which (I assume) would make my computer slow - I do not need all those backups - how do I stop that and maybe my computer will speed up