it should work with B1. Could you please share the product you are using and your configuration parameters in order to try to reproduce your processing?
In the band 1, the deep water reflectance is higher than on the other areas, what is a problem for the algorithm (It has to compute some logarithms so it discards the pixels where Reflectance-DeepReflectance is negative). I think that this is the problem in your image. Perhaps it is not always possible to use the algorithm with B1, where deep water reflectance can be higher than shallow water reflectance.
I am also struggling with the problem except it occurs regardless of the band combinations that are used, wondering if anyone has suggestions for how to at least get the B2/B3 combination to work.