I know this question exists here, but I tried every solution, but didnt work.
I have schema which has two properties, and second property will be displayed when first property is true. For this I used “options/dependencies”. I want to make second property required when first property is true.

    "authorizationNumber": {
      "type": "object",
      "format": "grid-strict",
      "required": ["firstProperty"],
      "properties": {
        "firstProperty": {
          "type": "boolean",
          "default": false,
          "options": {
            "grid_columns": 3
          }
        },
        "secondProperty": {
          "type": "array",
          "format": "select2",
          "uniqueItems": true,
          "minItems": 1,
          "items": {
            "type": "string",
            "$ref": "#/definitions/serviceCode"
          },
          "options": {
            "dependencies": {
              "firstProperty": true
            },
            "select2": {
              "closeOnSelect": true,
              "tags": false
            },
            "grid_columns": 4
          }
        }
      }
    }

I tried if/then/else as below:

    "authorizationNumber": {
      "type": "object",
      "format": "grid-strict",
      "required": ["firstProperty"],
      "if": {
        "properties": {
          "authorizationNumberAvailable":{
            "const": true
          }
        }
      },
      "then": {
        "required": ["secondProperty"]
      },
      "properties": {
        "firstProperty": {
        "type": "boolean",
        "default": false,
        "options": {
          "grid_columns": 3
        }
       },
      "secondProperty": {
        "type": "array",
        "format": "select2",
        "uniqueItems": true,
        "minItems": 1,
        "items": {
          "type": "string",
          "$ref": "#/definitions/serviceCode"
        },
        "options": {
          "dependencies": {
            "firstProperty": true
          },
          "select2": {
            "closeOnSelect": true,
            "tags": false
          },
          "grid_columns": 4
        }
      }
    }
  }

This does not give any errors, but it is not setting the “secondProperty” as required.
I also tried wrapping if/then with “allOf” as it is suggested one of the answers. To conclude, “secondProperty” should be available and marked as required when “firstProperty” is set to true.