iPhone iOS 18.2 can’t resolve hostnames when changing networks, possibly DoH problems

When I’m connected to home WiFi and leave the network, iPhone normally switches to mobile data. I can’t browse the web for some time or until I restart device.
I have installed some terminal application and I can ping NextDNS IP when that happens, but I can’t resolve web addresses, browse the web. 
I have set NextDNS on iPhone via app, it’s the same behavior with just Apple Configuration Profile Generator as it’s the same thing. I have tried. 
I think the problem is with DNS-over-HTTPS. I’m using MikroTik for home router and when I have set DNS-over-HTTPS, I had something  bad with certificate, “ssl handshake failed” or something from time to time, often enough that it was unusable. The solution was not to use DoH and put NextDNS IP addresses in ip/dns/settings/servers and linking my IP. 
On the other hand, Android devices in my family use DNS-over-TLS and they don’t have problem when changing from WiFi to mobile data. 
 

Sorry for long explanation. If someone knows how to solve this problem or how to use DNS-over-TLS on iPhone instead DoH, please help me.