diff --git a/extensions-builtin/Lora/networks.py b/extensions-builtin/Lora/networks.py
index 42b14dc23..360455f87 100644
--- a/extensions-builtin/Lora/networks.py
+++ b/extensions-builtin/Lora/networks.py
@@ -378,7 +378,10 @@ def network_apply_weights(self: Union[torch.nn.Conv2d, torch.nn.Linear, torch.nn
         self.network_weights_backup = weights_backup
 
     bias_backup = getattr(self, "network_bias_backup", None)
-    if bias_backup is None:
+    if bias_backup is None and wanted_names != ():
+        if current_names != ():
+            raise RuntimeError("no backup bias found and current bias are not unchanged")
+
         if isinstance(self, torch.nn.MultiheadAttention) and self.out_proj.bias is not None:
             bias_backup = self.out_proj.bias.to(devices.cpu, copy=True)
         elif getattr(self, 'bias', None) is not None: