diff --git a/NEWS.md b/NEWS.md
index 762df24359..9f4fe92385 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -10,6 +10,8 @@
 
 ## BUG FIXES
 
+* `ggplotly()` now handles discrete axes of a `facet_wrap` and `facet_grid` correctly when there is only one category in panels > 1 (#1577 and #1720).
+
 * `ggplotly()` now handles `element_blank()` and `factor()` labels in positional scales correctly (#1731 and #1772).
 
 # 4.9.2.1
diff --git a/R/utils.R b/R/utils.R
index 6fc2472f13..93dd1461b5 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -521,7 +521,7 @@ verify_attr <- function(proposed, schema, layoutAttr = FALSE) {
     
     # do the same for "sub-attributes"
     if (identical(role, "object") && is.recursive(proposed[[attr]])) {
-      proposed[[attr]] <- verify_attr(proposed[[attr]], schema[[attr]], layoutAttr = layoutAttr)
+      proposed[[attr]] <- verify_attr(proposed[[attr]], attrSchema, layoutAttr = layoutAttr)
     }
   }
   
diff --git a/tests/testthat/test-facet-axis.R b/tests/testthat/test-facet-axis.R
new file mode 100644
index 0000000000..62562c9319
--- /dev/null
+++ b/tests/testthat/test-facet-axis.R
@@ -0,0 +1,15 @@
+test_that("ggplotly does not break discrete x-axis with facet_yyyy in panels > 1 with only one category", {
+  d <- data.frame(cat = c("A", "A", "A"), pan = paste("Panel", c(1, 2, 2)))
+  gp <- ggplot(d, aes(cat)) +
+    geom_bar() +
+    facet_wrap(~pan)
+  L <- plotly_build(ggplotly(gp))
+  # tickvals, ticktext and categoryarray have class 'AsIs'
+  lapply(L$x$layout[c("xaxis", "xaxis2")], function(axis) {
+    expect_s3_class(axis$tickvals, "AsIs")
+    expect_s3_class(axis$ticktext, "AsIs")
+    expect_true(axis$ticktext == "A")
+    expect_s3_class(axis$categoryarray, "AsIs")
+    expect_true(axis$categoryarray == "A")
+  })
+})