diff --git a/common/common.cpp b/common/common.cpp
index 4873a27d..badc4317 100644
--- a/common/common.cpp
+++ b/common/common.cpp
@@ -1532,9 +1532,6 @@ bool gpt_params_find_arg(int argc, char ** argv, const std::string & arg, gpt_pa
                 ban_phrases.push_back(str);
             }
         }
-        std::sort(ban_phrases.begin(), ban_phrases.end(), [](const std::string& a, const std::string& b) {
-            return a.length() > b.length();
-            });
         params.ban_phrases = ban_phrases;
         return true;
     }
diff --git a/common/common.h b/common/common.h
index 58ffded1..55a56018 100644
--- a/common/common.h
+++ b/common/common.h
@@ -216,9 +216,9 @@ struct gpt_params {
 
     std::vector<std::string> in_files;     // all input files
     std::vector<std::string> antiprompt;   // strings upon which more user input is prompted (a.k.a. reverse prompts)
-    std::vector<std::string> ban_phrases;  //strings that are banned in generation
-    int32_t banned_n = 1;                 // number of tokens that are banned in the phrase
-    int32_t n_buffer;					   // number of token buffers for string ban
+    std::vector<std::string> ban_phrases;  // strings that are banned in generation
+    int32_t banned_n                 =  1; // number of tokens that are banned in the phrase
+    size_t n_buffer 				 =  0; // number of token buffers for string ban
 
     std::vector<llama_model_kv_override> kv_overrides;
     std::vector<llama_model_tensor_buft_override> tensor_buft_overrides;
diff --git a/examples/server/server-context.cpp b/examples/server/server-context.cpp
index dd5d4001..130d499e 100644
--- a/examples/server/server-context.cpp
+++ b/examples/server/server-context.cpp
@@ -1143,21 +1143,28 @@ bool server_context::launch_slot_with_task(server_slot& slot, server_task& task)
             std::sort(slot.ban_phrases.begin(), slot.ban_phrases.end(), [](const std::string& a, const std::string& b) {
                 return a.length() > b.length();
                 });
-        }
-        else if (params_base.ban_phrases.size()>0 && params_base.n_buffer == 0) { 
-			slot.ban_phrases.clear();
-            for (const auto & val : params_base.ban_phrases) {
-                if (!val.empty()) {
-                    std::string s = string_lower(val);
-                    auto ban_tokens = common_tokenize(llama_get_model(ctx), s, false, true);
-                    if (ban_tokens.size() > slot.n_buffer) {
-                        slot.n_buffer = ban_tokens.size();
+        } else if (params_base.ban_phrases.size() > 0) {
+            if (params_base.n_buffer == 0) {
+                slot.ban_phrases.clear();
+                std::sort(params_base.ban_phrases.begin(), params_base.ban_phrases.end(), [](const std::string & a, const std::string & b) {
+                    return a.length() > b.length();
+                    });
+                for (auto & val : params_base.ban_phrases) {
+                    if (!val.empty()) {
+                        val = string_lower(val);
+                        auto ban_tokens = common_tokenize(llama_get_model(ctx), val, false, true);
+                        if (ban_tokens.size() > slot.n_buffer) {
+                            slot.n_buffer = ban_tokens.size();
+                        }
+                        slot.ban_phrases.push_back(val);
                     }
-                    slot.ban_phrases.push_back(s);
-                }
+                }              
+                slot.n_buffer = slot.n_buffer + 3; // extra buffer in case
+                params_base.n_buffer = slot.n_buffer;
+            } else {
+                slot.ban_phrases = params_base.ban_phrases;
+                slot.n_buffer = params_base.n_buffer;
             }
-            params_base.n_buffer = slot.n_buffer + 3;
-            slot.n_buffer = slot.n_buffer + 3; // extra buffer in case
         }
 		slot.logit_bias = slot.sparams.logit_bias; // keep a copy to restore
         slot.ban_phrases_bias = json_value(data, "banned_bias", params_base.ban_phrases_bias);
diff --git a/examples/server/server-context.h b/examples/server/server-context.h
index fc2dc029..a9d9573c 100644
--- a/examples/server/server-context.h
+++ b/examples/server/server-context.h
@@ -84,7 +84,7 @@ struct server_slot {
     stop_type stop;
 
     // For context rewind/ token buffer
-    int32_t n_buffer = 0;
+    size_t n_buffer = 0;
     int32_t rewind_count = 0;
     bool rewind_status = false;
     std::unordered_map<llama_token, float> logit_bias;