diff --git a/post.go b/post.go
index a027d2a..cc72da9 100644
--- a/post.go
+++ b/post.go
@@ -29,7 +29,7 @@ func (c *Client) do(ctx context.Context, form url.Values) ([]byte, error) {
 	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
 
 	resp, err := c.httpClient().Do(req)
-	if err != nil {
+	if (err != nil) || (resp == nil) {
 		return nil, fmt.Errorf("failed to contact API: %w", err)
 	}
 
diff --git a/post_test.go b/post_test.go
index 66d1b89..47a06aa 100644
--- a/post_test.go
+++ b/post_test.go
@@ -135,7 +135,7 @@ func TestUpdateOK(t *testing.T) {
 	_, err := client.Update(ctx, records)
 	if err != nil {
 		var netErr net.Error
-		if errors.As(err, &netErr) && netErr.Timeout() {
+		if errors.As(err, &netErr) && (netErr != nil) && netErr.Timeout() {
 			t.Errorf("Timeoutsss: %s", netErr)
 		} else {
 			t.Errorf("Successful post should return OK but failed with error: %s", err)