What I found early on using HA-Bridge was you need a reliably quick network. Any slow down will cause Alexa to fail.
Play with the "UPNP send delay" setting in the HA-Bridge config page. The default setting works most of the time but I found without ajusting this at my offgrid place Alexa would fail to activate a device even after successfully adding it. I also had to readjust this setting this summer when my DSL connection speed was increased. Interestingly our city broadband connection speed just increased (after a yearly squabble with our ISP) and I didn't need to addjust this. However Alexa responces are faster now.
I still strongly suggest you read throught the issues at the HA-Bridge github, look through both the current and resolved issues.