don't seek on nil options.RawBody
diff --git a/provider_client.go b/provider_client.go
index e5b75b2..4eeec59 100644
--- a/provider_client.go
+++ b/provider_client.go
@@ -189,7 +189,9 @@
 			if err != nil {
 				return nil, fmt.Errorf("Error trying to re-authenticate: %s", err)
 			}
-			options.RawBody.Seek(0, 0)
+			if options.RawBody != nil {
+				options.RawBody.Seek(0, 0)
+			}
 			resp, err = client.Request(method, url, options)
 			if err != nil {
 				return nil, fmt.Errorf("Successfully re-authenticated, but got error executing request: %s", err)