Trying to get the app to connect and manage the bulb can be a pain, trick is to turn the light on and off very fast about 5 to six times, and I mean fast, if you slowly turn it off then back on it won't go into pairing mode, that is when the light blinks off and on.
I own several different Teckin products and they all work flawlessly. I highly recommend them.
Good while they work but I had to replace 2 after only a year. I expected these to last longer.
Excellent product only problem is all light features in Teckin App should be available Alexa or Google particularly the "scenes" options.