Error: failed space/blob/add invocation

[0xExp-po]

      const client = await Client.create();
      const apiUrl = `/api/w3up-delegation`;

      const response = await fetch(apiUrl, {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ did: client.agent.did() }),
      });
      const data = await response.arrayBuffer();

      const delegation = await Delegation.extract(new Uint8Array(data));
      if (!delegation.ok) {
        throw new Error("Failed to extract delegation", {
          cause: delegation.error,
        });
      }


      const space = await client.addSpace(delegation.ok);
      client.setCurrentSpace(space.did());
      
      ...
      const directoryCid = await client.uploadDirectory(files);

I uploaded directory directly in the front end side by using the delegation.
This function was working well but suddenly an error started occurs.

Error: failed space/blob/add invocation
    at add12 (@web3-storage_w3up-client.js?v=08ca7a59:18688:11)
    at async Object.transform (@web3-storage_w3up-client.js?v=08ca7a59:26845:9)

I've confirmed this error occurs in the last line(upload directory function).
How can I resolve this issue.