diff --git a/components/alibi-detect-server/adserver/ad_model.py b/components/alibi-detect-server/adserver/ad_model.py
index 0a92370f65..53d3cc8019 100644
--- a/components/alibi-detect-server/adserver/ad_model.py
+++ b/components/alibi-detect-server/adserver/ad_model.py
@@ -4,6 +4,7 @@
 import numpy as np
 from adserver.constants import HEADER_RETURN_INSTANCE_SCORE
 from .numpy_encoder import NumpyEncoder
+from adserver.protocols.util import read_inputs_as_numpy
 from alibi_detect.utils.saving import load_detector, Data
 from adserver.base import CEModel, ModelResponse
 from adserver.base.storage import download_model
@@ -60,7 +61,7 @@ def process_event(self, inputs: Union[List, Dict], headers: Dict) -> ModelRespon
         logging.info(str(headers))
         logging.info("----")
         try:
-            X = np.array(inputs)
+            X = read_inputs_as_numpy(inputs)
         except Exception as e:
             raise Exception(
                 "Failed to initialize NumPy array from inputs: %s, %s" % (e, inputs)
diff --git a/components/alibi-detect-server/adserver/od_model.py b/components/alibi-detect-server/adserver/od_model.py
index 56e66262c0..3c1b09f6f5 100644
--- a/components/alibi-detect-server/adserver/od_model.py
+++ b/components/alibi-detect-server/adserver/od_model.py
@@ -4,6 +4,7 @@
 import logging
 import numpy as np
 from .numpy_encoder import NumpyEncoder
+from adserver.protocols.util import read_inputs_as_numpy
 from adserver.base import CEModel, ModelResponse
 from alibi_detect.utils.saving import load_detector, Data
 from adserver.base.storage import download_model
@@ -85,7 +86,7 @@ def process_event(self, inputs: Union[List, Dict], headers: Dict) -> Optional[Mo
         logging.info(str(headers))
         logging.info("----")
         try:
-            X = np.array(inputs)
+            X = read_inputs_as_numpy(inputs)
         except Exception as e:
             raise Exception(
                 "Failed to initialize NumPy array from inputs: %s, %s" % (e, inputs)
diff --git a/components/alibi-detect-server/adserver/protocols/util.py b/components/alibi-detect-server/adserver/protocols/util.py
index 22c89923b1..4e5fa5421e 100644
--- a/components/alibi-detect-server/adserver/protocols/util.py
+++ b/components/alibi-detect-server/adserver/protocols/util.py
@@ -1,5 +1,5 @@
 import json
-
+from typing import List, Dict, Union
 import numpy as np
 
 
@@ -35,3 +35,17 @@ def default(self, obj):  # pylint: disable=arguments-differ,method-hidden
         elif isinstance(obj, (np.ndarray,)):
             return obj.tolist()
         return json.JSONEncoder.default(self, obj)
+
+
+def read_inputs_as_numpy(inputs: Union[List, Dict]) -> np.ndarray:
+    """
+    Read payload inputs as np.ndarray enforcing float32/int32 dtypes.
+    See: https://github.com/SeldonIO/seldon-core/issues/3940 for details.
+    """
+    x = np.array(inputs)
+    if x.dtype == np.float64:
+        return x.astype(np.float32)
+    elif x.dtype == np.int64:
+        return x.astype(np.int32)
+    else:
+        return x