diff --git a/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_gtp.c b/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_gtp.c
index c1d2a0f0b7..31d96433c1 100644
--- a/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_gtp.c
+++ b/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_gtp.c
@@ -93,5 +93,7 @@ void read_gtp_setup_sm(void* data)
 sm_ag_if_ans_t write_ctrl_gtp_sm(void const* src)
 {
   assert(src != NULL);
-  assert(0 !=0 && "Not supported");
+  printf("write_ctrl callback for GTP SM: operation not supported\n");
+  sm_ag_if_ans_t ans = {0};
+  return ans;
 }
diff --git a/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_mac.c b/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_mac.c
index 56633f53e0..3e3caac9fe 100644
--- a/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_mac.c
+++ b/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_mac.c
@@ -123,6 +123,8 @@ void read_mac_setup_sm(void* data)
 sm_ag_if_ans_t write_ctrl_mac_sm(void const* data)
 {
   assert(data != NULL);
-  assert(0 !=0 && "Not supported");
+  printf("write_ctrl callback for MAC SM: operation not supported\n");
+  sm_ag_if_ans_t ans = {0};
+  return ans;
 }
 
diff --git a/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_pdcp.c b/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_pdcp.c
index 6c8c1268a7..21b2e0f41c 100644
--- a/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_pdcp.c
+++ b/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_pdcp.c
@@ -152,7 +152,7 @@ sm_ag_if_ans_t write_ctrl_pdcp_sm(void const* data)
 {
   assert(data != NULL);
 //  assert(data->type == PDCP_CTRL_REQ_V0 );
-  assert(0 !=0 && "Not supported");
+  printf("write_ctrl callback for PDCP SM: operation not supported\n");
   sm_ag_if_ans_t ans = {0};
   return ans;
 }
diff --git a/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_rlc.c b/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_rlc.c
index d78c103fbf..08b070eb8d 100644
--- a/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_rlc.c
+++ b/openair2/E2AP/RAN_FUNCTION/CUSTOMIZED/ran_func_rlc.c
@@ -174,6 +174,8 @@ void read_rlc_setup_sm(void* data)
 sm_ag_if_ans_t write_ctrl_rlc_sm(void const* data)
 {
   (void)data;
-  assert(0!=0 && "Not supported");
+  printf("write_ctrl callback for RLC SM: operation not supported\n");
+  sm_ag_if_ans_t ans = {0};
+  return ans;
 }
 
diff --git a/openair2/E2AP/RAN_FUNCTION/O-RAN/ran_func_kpm.c b/openair2/E2AP/RAN_FUNCTION/O-RAN/ran_func_kpm.c
index 748b4f7d29..40371df046 100644
--- a/openair2/E2AP/RAN_FUNCTION/O-RAN/ran_func_kpm.c
+++ b/openair2/E2AP/RAN_FUNCTION/O-RAN/ran_func_kpm.c
@@ -537,7 +537,7 @@ void read_kpm_setup_sm(void* e2ap)
 
 sm_ag_if_ans_t write_ctrl_kpm_sm(void const* src)
 {
-  assert(0 !=0 && "Not supported");
+  printf("write_ctrl callback for KPM SM: operation not supported\n");
   (void)src;
   sm_ag_if_ans_t ans = {0};
   return ans;