diff --git a/R/utils-date_time_parse.R b/R/utils-date_time_parse.R
index 619945e..6e19a53 100644
--- a/R/utils-date_time_parse.R
+++ b/R/utils-date_time_parse.R
@@ -121,7 +121,7 @@ long_tzid_to_tz_str <- function(long_tzid, input_dt) {
     tzdb$zone_name == long_tzid, c("date_start", "gmt_offset_h")]
 
   if (nrow(tzdb_entries_tzid) == 0L) {
-    return(NA_character_)
+    return(NULL)
   }
 
   input_date <- as.Date(input_dt)
diff --git a/tests/testthat/test-fdf_ftf.R b/tests/testthat/test-fdf_ftf.R
index 1efc8e8..c44854a 100644
--- a/tests/testthat/test-fdf_ftf.R
+++ b/tests/testthat/test-fdf_ftf.R
@@ -196,8 +196,24 @@ test_that("`flex_*_lst` can be used in `fdt()`", {
 
 test_that("fdt() works in all contexts", {
   expect_equal(
-    bigD::fdt("2024-03-01", format = "GyMMMEd", use_tz = "America/Toronto"),
+    fdt("2024-03-01", format = "GyMMMEd", use_tz = "America/Toronto"),
     "AD2024MarFri1"
   )
-
+  # Copy of a test in gt
+  expect_equal(
+    fdt(as.POSIXlt(
+      c(
+        "1970-01-01 15:35:00", "1970-01-01 16:36:00", "1970-01-01 17:37:00",
+        "1970-01-01 18:38:00", "1970-01-01 19:39:00"
+      ),
+      tz = "GMT"
+      ),
+      format = "EBhms"
+    ),
+    c(
+      "Thu 3:35:00 in the afternoon", "Thu 4:36:00 in the afternoon",
+      "Thu 5:37:00 in the afternoon", "Thu 6:38:00 in the evening",
+      "Thu 7:39:00 in the evening"
+    )
+  )
 })