Issues with Sengled classic bulbs pairing

Looking for advice. I have 3 Sengled classic A19 bulbs that I had paired with my Echo and Smartthings hub. Today I changed out my hub for another one, and before I did so I removed/forgot all the things associated with it (including these bulbs). I also removed them from Alexa.

After replacing the old Smartthings hub with the new one and setting it up again, I am unable to get these bulbs into pairing mode again for discovery. I tried turning the lamp I have them in on and off quickly 10 times as indicated on their website, but I can never get the flashing pairing mode to activate like they did when I first installed them. These bulbs do not have a pairing button on them. I am not signed up with a Sengled account either (which didn’t matter when I initially set them up).

Does anyone know what I am doing wrong?