Question: How can I contract the Christoffel with a vector?

When trying to contract the Christoffel with some vector

DGsetup([r, phi], M);
g := evalDG(dr &t dr + r^2 * dphi &t dphi);
ContractIndices(Christoffel(g), D_phi, [[2, 1]]);

I get the following error:

Error, (in DifferentialGeometry:-Tensor:-ContractIndices) expected 1st argument to be a tensor. Received: _DG([["connection", M, [["con_bas", "cov_bas", "cov_bas"], []]], [`...`]])

What can I do about that?

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