PiHole Next DNS Issues

On my Pi:

1. Ran the official NextDNS installation script - sh -c "$(curl -sL https://nextdns.io/install)"

2. entered in profile ID

3. Answered no when prompted for router and all others except report device name

4. went into sudo nano /etc/nextdns.conf and modified listen to listen 127.0.0.1:5353 ( wrote it and saved ) - confirmed - restarted the service

web browser on an endpoint :

1. logged into pi hole admin

2. settings > DNS

3. unchecked all upstream DNS servers

4. first box - custom - entered in - 127.0.0.1#5353

5. saved

6. enabled DNSSEC pihole via settings > DNS > advanced DNS > checked off use DNSSEC and saved

7. confirmed public ip is linked

8. log into router - update DNS form auto to pihole ip

9. pause Wi-Fi, resume

10. clients connect - verify this in pi hole

11.  

    • visit test.nextdns.io - staus is ok and protocol is DOH

12. within 10 minutes - devices stop responding

any help would be appreciated on why this happens - am I missing steps?