Replace an experiment's arms

{  "data": [    {      "id": "exp_var_w2e7h7d2k9m4x1c6v8b3n5q0",      "name": "Monthly first",      "isControl": true,      "weightPercentage": 50,      "placements": [        {          "paywallLocationId": "pw_loc_m4x1c6v8b3n5q0w2e7h7d2k9",          "paywallId": "pw_r3t6y9u2i5o8p1a4s7d0f3g6"        }      ]    },    {      "id": "exp_var_n5q0w2e7h7d2k9m4x1c6v8b3",      "name": "Annual first",      "isControl": false,      "weightPercentage": 50,      "placements": [        {          "paywallLocationId": "pw_loc_m4x1c6v8b3n5q0w2e7h7d2k9",          "paywallId": "pw_h7d2k9m4x1c6v8b3n5q0w2e7"        }      ]    }  ],  "pageInfo": {    "endCursor": null,    "hasNextPage": false  }}

{  "error": {    "type": "unauthenticated",    "code": "invalid_api_key",    "message": "This secret key is not valid."  }}

{  "error": {    "type": "permission_denied",    "code": "permission_denied",    "message": "Insufficient permissions."  }}

{  "error": {    "type": "not_found",    "code": "project_not_found",    "message": "There is no project proj_tz4a98xxat96iws9zmbrgj3a, or this credential cannot use it.",    "param": "projectId"  }}

{  "error": {    "type": "conflict",    "code": "experiment_variants_locked",    "message": "This experiment is running, so its arms cannot change; pause it first."  }}

{  "error": {    "type": "internal",    "code": "internal_error",    "message": "Something went wrong on our side. Try again, and contact support with the Request-Id header if it keeps failing."  }}