cannot access relay web ui (or by other means)

Hi everyone,

i just received a couple of devices from Athom. I managed to install the LED Bulbs and the switches/plugs - altough I bricked one LED when trying to use official tasmota.bin.gz release (followed the description in this board).

Now, with the relays it is entirely different. There is a totally different firmware installed and while I manage to configure the WLAN, I never get access to the web ui. The router shows an IP/DHCP lease, but the device start blinking now and then (did not figure the pattern yet). I could not access any web ui and thus the device appears unusable ... any hints?

I did a nmap scan that showed only one open port:

PORT STATE SERVICE REASON VERSION

5556/tcp open freeciv? syn-ack ttl 255

1 service unrecognized despite returning data. If you know the service/version, please submit the following fingerprint

I bought this device, so that i can use and customize it with tasmota firmware ... that said, is there a good way of opening the plastic cover to get to the esp chip?

Best,

Hannes

PS: the network it is connected to does not have internet access