Sudden Amazon Echo Skill errors

just spotted this in my logs

app:352021-03-16 07:52:05.794 pm errorError making Call to Alexa message gateway: {"header":{"namespace":"System","name":"Exception","messageId":"ASRLS_b0547e73-21be-4a83-8ef2-c9eb2c7d26dd_1615938728208.0..ASRLS_b0547e73-21be-4a83-8ef2-c9eb2c7d26dd_1615938728208"},"payload":{"code":"INVALID_REQUEST_EXCEPTION","description":"Cannot read the request payload as: Cannot construct instance of com.amazon.iota.driver.v3.StateReportProperty, problem: value\n at [Source: UNKNOWN; line: -1, column: -1] (through reference chain: com.amazon.iota.driver.directive.v3.MessageEnvelope$V3Builder["context"]->com.amazon.iota.driver.directive.v3.Context["properties"]->com.amazon.iota.driver.v3.StateReportPropertyArray[3])"}}