diff --git a/R/CST_MergeDims.R b/R/CST_MergeDims.R
index dabdc57f3ae0aafd543f45d9f2594acdd5738c88..6756ce7937adc9527aa8482c049f0c10b64951a8 100644
--- a/R/CST_MergeDims.R
+++ b/R/CST_MergeDims.R
@@ -53,7 +53,8 @@ CST_MergeDims <- function(data, merge_dims = c('ftime', 'monthly'),
 
   # attrs
   if (all(merge_dims %in% names(dim(data$attrs$Dates)))) {
-    dim(data$attrs$Dates) <- dim(data$data)[rename_dim]
+    data$attrs$Dates <- MergeDims(data$attrs$Dates, merge_dims = merge_dims,
+                                  rename_dim = rename_dim, na.rm = na.rm)
   } else if (any(merge_dims %in% names(dim(data$attrs$Dates)))) {
     warning("The dimensions of 'Dates' array will be different from ",
             "the temporal dimensions in 'data'. Parameter 'merge_dims' ",