Hot to configure STUN on kubernetes?

I've deployed coder to my kubernetes cluster using helm chart but DERP is shown as unhealthy(ESTUN01 No STUN servers are available.). What I'm missing in configuration? It is strange to have IPv6 red too because cluster has ipv6 netcheck: netcheck.runProbe: got STUN response for 1004stun0 from 46.4.36.142:39538 (9d0a6427fde4dd8c8068781b) in 5.429369ms netcheck: netcheck.runProbe: got STUN response for 1004stun0 from 46.4.36.142:39538 (477fdf472350cf0d1ff18396) in 5.299449ms netcheck: netcheck.runProbe: got STUN response for 1004stun0 from 46.4.36.142:39538 (3a797439a786b219bd4e7982) in 5.238018ms netcheck: netcheck.runProbe: got STUN response for 1000stun0 from 46.4.36.142:39538 (0bd0cd290cdc6027c056a8b1) in 5.293097ms netcheck: netcheck.runProbe: got STUN response for 1001stun0 from 46.4.36.142:39538 (3327e88b54569309d559229b) in 81.721878ms netcheck: [v1] measuring ICMP latency of coder (999): no address for node 999b netcheck: netcheck.runProbe: got STUN response for 1001stun0 from 46.4.36.142:39538 (85baad7375e730a1f6ffbb96) in 81.742204ms netcheck: netcheck.runProbe: got STUN response for 1001stun0 from 46.4.36.142:39538 (fbd49d855a8cf6de0a8c069f) in 81.765689ms netcheck: [v1] report: udp=true v6=false v6os=true mapvarydest=false hair=false portmap= v4a=46.4.36.142:39538 derp=999 derpdist=999v4:1ms