SolverFailureError: quadratic must be a sequence of length 93
I'm running into an issue where I suddenly start seeing solver failures halfway through running a jupyter notebook. I'm calling the solver inside a loop, and it runs successfully 38 times and then always fails on the 39th time, with the error 'SolverFailureError: quadratic must be a sequence of length 93.'
I'm having difficulty diagnosing the problem, given that the binary quadratic model is of the same size and structure as it was in the previous 38 runs so there's no reason the embedding should suddenly stop working. Nothing seems obviously different about the 39th run.
Does anyone know what this error message might mean?