I had a similar issue, don’t know if it was the same , what I’ve done was stoping thinger and starting again, it turns off wifi and when it turns on connects again.
You stop it with
thing.stop();
Of course you need to stop call thinger.handle(); so it can turn it off wifi and call it again after some seconds, I stop it by 10 seconds and it works fine.
Let you the post where it was discussed about it
https://community.thinger.io/t/disconnect-and-reconnect-esp8266/1509/3