diff --git a/R/downloads.R b/R/downloads.R
index bde50a24..7fef1389 100644
--- a/R/downloads.R
+++ b/R/downloads.R
@@ -33,8 +33,9 @@ download <- function(model_output, type, path_results, input, language = NULL) {
     out <- naomi::hintr_prepare_agyw_download(model_output, input$pjnz,
                                               download_path)
   } else if (type == "datapack") {
-    model_fit_id <- input$state$model_fit$id
-    calibrate_id <- input$state$calibrate$id
+    state_json <- jsonlite::fromJSON(input$state, simplifyVector = FALSE)
+    model_fit_id <- state_json$model_fit$id
+    calibrate_id <- state_json$calibrate$id
     ids <- data.frame(c("model_fit", "calibrate"),
                       c(model_fit_id, calibrate_id))
     out <- naomi::hintr_prepare_datapack_download(model_output,
diff --git a/tests/testthat/test-01-endpoints-download.R b/tests/testthat/test-01-endpoints-download.R
index f1201c4c..473ea9c3 100644
--- a/tests/testthat/test-01-endpoints-download.R
+++ b/tests/testthat/test-01-endpoints-download.R
@@ -1035,7 +1035,9 @@ test_that("datapack download returns bytes", {
 
   ## Submit download request
   submit <- endpoint_download_submit(q$queue)
-  submit_response <- submit$run(q$calibrate_id, "datapack")
+  payload <- setup_payload_download_request(include_vmmc = TRUE,
+                                            include_notes = FALSE)
+  submit_response <- submit$run(q$calibrate_id, "datapack", payload)
 
   expect_equal(submit_response$status_code, 200)
   expect_true(!is.null(submit_response$data$id))