tf2onnx Unsupported ops: Counter({'SigmoidGrad': 2, 'StridedSliceGrad': 1}) when converting saved model to onnx file

Question

i´m trying to convert a tensorflow model saved to a onnx file to be diggested by c#. I´m using tf2oonx

python -m tf2onnx.convert --saved-model "C:\\Users\\goncalo\\OneDrive\\Área de Trabalho\\cyclop\\My_Class_Model" --output "C:\\Users\\goncalo\\OneDrive\\Área de Trabalho\\cyclop\\My_Class_Model_opt_16.onnx" --opset 15

and it gives me this erros:

2022-05-03 12:01:16,131 - ERROR - Tensorflow op [StatefulPartitionedCall/gradient_tape/grad_cam__class/strided_slice/StridedSliceGrad: StridedSliceGrad] is not supported
2022-05-03 12:01:16,131 - ERROR - Tensorflow op [StatefulPartitionedCall/gradient_tape/grad_cam__class/model/Head_out_fc/Sigmoid/SigmoidGrad: SigmoidGrad] is not supported
2022-05-03 12:01:16,134 - ERROR - Tensorflow op [StatefulPartitionedCall/gradient_tape/grad_cam__class/model/Head_fc/swish_activation_1/Sigmoid/SigmoidGrad: SigmoidGrad] is not supported
2022-05-03 12:01:16,149 - ERROR - Unsupported ops: Counter({'SigmoidGrad': 2, 'StridedSliceGrad': 1})

And i´m a bit stucked. Someone?

Thanks