estimate_cost() raises exception " 'NoneType' object is not iterable "

[quantex]

azure-quantum: 0.24.210930 qiskit: 0.36.1 qiskit-ignis: 0.7.0

Simple steps to reproduce follow:

import qiskit.circuit as qc
from qiskit.ignis import verification as ver
from azure.quantum.qiskit import AzureQuantumProvider
import schur

provider = AzureQuantumProvider (
    resource_id = "/subscriptions/[id]/resourceGroups/Azure-quantum-credits/providers/Microsoft.Quantum/Workspaces/EntangledNetworksQuantumCredits",
    location = "eastus"
)
backend = provider.get_backend('quantinuum.hqs-lt-s1')

qr = qc.QuantumRegister(3,'qr_main')
uc = qc.QuantumCircuit(qr)

# Compose a quantum circuit
uc = schur.genCompression(uc)

# Construct tomography job list with Ignis
uc_tomo = ver.tomography.state_tomography_circuits(uc, [0,1,2])

# Estimate runtime cost
nShots = 512
cost = []
for idx,job in enumerate(jobs):
    cost.append(backend.estimate_cost(job,shots=nShots))
    print(cost[idx].estimated_total)

In the penultimate line, backend.estimate_cost() raises the error: 'NoneType' object is not iterable.

We know our circuit set (variable name uc) runs fine on various backends, including on other Azure backends (e.g. honeywell.hqs-lt-s1-apival and honeywell.hqs-lt-s1-sim as of azure_quantum-0.23.195983).