diff --git a/comfy/samplers.py b/comfy/samplers.py
index 9f571ece9..29e6bffb3 100755
--- a/comfy/samplers.py
+++ b/comfy/samplers.py
@@ -997,7 +997,7 @@ class KSAMPLER(Sampler):
         def k_callback(x):
             nonlocal first_step
             if first_step:
-                detail("First sampler step: model=%s sampler=%s step=%s total_steps=%s cfg=%s seed=%s sigma=%s sigma_hat=%s latent_shape=%s denoised_shape=%s", model_wrap.model_patcher.model.__class__.__name__, self.sampler_function.__name__, x["i"], total_steps, model_wrap.cfg, extra_args.get("seed"), x.get("sigma"), x.get("sigma_hat"), tuple(x["x"].shape), tuple(x["denoised"].shape))
+                detail("First sampler step: model=%s sampler=%s step=%s total_steps=%s cfg=%s seed=%s sigma=%s sigma_hat=%s latent_shape=%s denoised_shape=%s", model_wrap.model_patcher.model.__class__.__name__, getattr(self.sampler_function, "__name__", "unknown"), x["i"], total_steps, model_wrap.cfg, extra_args.get("seed"), x.get("sigma"), x.get("sigma_hat"), tuple(x["x"].shape), tuple(x["denoised"].shape))
                 first_step = False
             if callback is not None:
                 callback(x["i"], x["denoised"], x["x"], total_steps)