50amp splitter to30 fails to split

[chefojfc]

Hello
I have been using a 50amp to two 30 amp lines all year
After a recent sail I reconnected and only one line lights up
I disconnected everything g at dock and reconnected turned the 50 back in
Still only one line
I did make sure the cables to boat worked. By plugging into separate 30 am dock outlet
It’s not the cables
The splitter is only 1 year old
Any thoughts
Can these splitters go bad?

[chefojfc]

As a follow up here the 50 amp receptacle at dock was malfunctioning
Splitter was fine