IBS-M2 Won't Connect to WIFI

So I had it connected and then it disconnected. So I know I have the write 2.4 wifi etc. I can’t get it to reconnect again. Any ideas?

Please check if the settings of the router have been changed? Please make sure there is no limit on the number of connected devices to the router.
Please place the IBS-M2 next to the router.
If it still does not restore the connection after waiting for a while, please delete the offline IBS-M2 in the app.
Please make sure your phone is connected to the 2.4GHz wifi. Please reconnect the IBS-M2. Will it work?