diff --git a/R/get_linear_predictors.R b/R/get_linear_predictors.R
index 33fc093b..b8942b72 100644
--- a/R/get_linear_predictors.R
+++ b/R/get_linear_predictors.R
@@ -10,7 +10,7 @@ obs_Xp_matrix = function(newdata, mgcv_model){
     testdat <- data.frame(time = newdata$time)
 
     terms_include <- insight::find_predictors(mgcv_model)$conditional
-    if(any(terms_include %in% names(trend_test) == FALSE)){
+    if(any(terms_include %in% names(newdata) == FALSE)){
       stop('not all required variables have been supplied in newdata!',
            call. = FALSE)
     }
diff --git a/src/mvgam.dll b/src/mvgam.dll
index fe64d771..498079f1 100644
Binary files a/src/mvgam.dll and b/src/mvgam.dll differ
diff --git a/tests/testthat/Rplots.pdf b/tests/testthat/Rplots.pdf
index 47f94e2c..5d576f9e 100644
Binary files a/tests/testthat/Rplots.pdf and b/tests/testthat/Rplots.pdf differ