I just got mine from cointaker and you always have to bend the connectors on the bulb out, to make proper contact. But you also have to make sure that it is inserted the right direction.
The 555 LED bulbs will only work one way as they are polarized, so if you bent the bulb connectors out, plug in the bulb and it doesn't work... pull it out, and turn it around to fit in the socket 180 degrees and it will work.
I have a bigger problem with the #44 bulb I have to file almost all of the middle connections on the bulbs down to fit in the socket. They are usually so tight that forcing the bulb to fit cracks the LED element connections inside the bulb.
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