diff --git a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_RA.c b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_RA.c
index e186b7d514..71ccd6c98b 100644
--- a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_RA.c
+++ b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_RA.c
@@ -1597,12 +1597,15 @@ void nr_generate_Msg4(module_id_t module_idP, int CC_id, frame_t frameP, sub_fra
     uint8_t tb_scaling = 0;
     uint16_t *vrb_map = cc[CC_id].vrb_map;
     do {
-      rbSize++;
+      if(rbSize < BWPSize)
+        rbSize++;
+      else
+        mcsIndex++;
       LOG_D(NR_MAC,"Calling nr_compute_tbs with N_PRB_DMRS %d, N_DMRS_SLOT %d\n",N_PRB_DMRS,N_DMRS_SLOT);
       harq->tb_size = nr_compute_tbs(nr_get_Qm_dl(mcsIndex, mcsTableIdx),
-                           nr_get_code_rate_dl(mcsIndex, mcsTableIdx),
-                           rbSize, nrOfSymbols, N_PRB_DMRS * N_DMRS_SLOT, 0, tb_scaling,1) >> 3;
-    } while (rbSize < BWPSize && harq->tb_size < ra->mac_pdu_length);
+                                     nr_get_code_rate_dl(mcsIndex, mcsTableIdx),
+                                     rbSize, nrOfSymbols, N_PRB_DMRS * N_DMRS_SLOT, 0, tb_scaling,1) >> 3;
+    } while (harq->tb_size < ra->mac_pdu_length);
 
     int i = 0;
     while ((i < rbSize) && (rbStart + rbSize <= BWPSize)) {