diff --git a/app/src/substrate_dispatch_V2.c b/app/src/substrate_dispatch_V2.c
index 231aad4..260a4e3 100644
--- a/app/src/substrate_dispatch_V2.c
+++ b/app/src/substrate_dispatch_V2.c
@@ -1210,7 +1210,7 @@ __Z_INLINE parser_error_t _readMethod_bounties_propose_bounty_V2(
 __Z_INLINE parser_error_t _readMethod_bounties_approve_bounty_V2(
     parser_context_t *c, pd_bounties_approve_bounty_V2_t *m)
 {
-    CHECK_ERROR(_readCompactu32(c, &m->bounty_id))
+    CHECK_ERROR(_readCompactBountyIndex_V2(c, &m->bounty_id))
     return parser_ok;
 }
 
@@ -6293,7 +6293,7 @@ parser_error_t _getMethod_ItemValue_V2(
         switch (itemIdx)
         {
         case 0: /* bounties_approve_bounty_V2 - bounty_id */;
-            return _toStringCompactu32(
+            return _toStringCompactBountyIndex_V2(
                 &m->basic.bounties_approve_bounty_V2.bounty_id,
                 outValue, outValueLen,
                 pageIdx, pageCount);
diff --git a/app/src/substrate_functions_V2.h b/app/src/substrate_functions_V2.h
index 3bec343..29ff3aa 100644
--- a/app/src/substrate_functions_V2.h
+++ b/app/src/substrate_functions_V2.h
@@ -121,6 +121,7 @@ parser_error_t _readschedulePeriodBlockNumber_V2(parser_context_t* c, pd_schedul
 parser_error_t _readschedulePriority_V2(parser_context_t* c, pd_schedulePriority_V2_t* v);
 parser_error_t _readAccountIdLookupOfT_V2(parser_context_t* c, pd_AccountIdLookupOfT_V2_t* v);
 parser_error_t _readOptionCompactu128_V2(parser_context_t* c, pd_OptionCompactu128_V2_t* v);
+parser_error_t _readCompactBountyIndex_V2(parser_context_t* c, pd_CompactBountyIndex_V2_t* v);
 
 // toString functions
 parser_error_t _toStringAccountId_V2(
@@ -158,6 +159,13 @@ parser_error_t _toStringAccountVote_V2(
     uint8_t pageIdx,
     uint8_t* pageCount);
 
+parser_error_t _toStringCompactBountyIndex_V2(
+    const pd_CompactBountyIndex_V2_t* v,
+    char* outValue,
+    uint16_t outValueLen,
+    uint8_t pageIdx,
+    uint8_t* pageCount);
+
 parser_error_t _toStringAuthorityIdasRuntimeAppPublicSignature_V2(
     const pd_AuthorityIdasRuntimeAppPublicSignature_V2_t* v,
     char* outValue,
diff --git a/app/src/substrate_methods_V2.h b/app/src/substrate_methods_V2.h
index 971948c..087af58 100644
--- a/app/src/substrate_methods_V2.h
+++ b/app/src/substrate_methods_V2.h
@@ -880,7 +880,7 @@ typedef struct {
 
 #define PD_CALL_BOUNTIES_APPROVE_BOUNTY_V2 1
 typedef struct {
-    pd_Compactu32_t bounty_id;
+    pd_CompactBountyIndex_V2_t bounty_id;
 } pd_bounties_approve_bounty_V2_t;
 
 #define PD_CALL_BOUNTIES_PROPOSE_CURATOR_V2 2
diff --git a/app/src/substrate_types_V2.c b/app/src/substrate_types_V2.c
index 468ef01..efd37f0 100644
--- a/app/src/substrate_types_V2.c
+++ b/app/src/substrate_types_V2.c
@@ -49,6 +49,11 @@ parser_error_t _readAccountVoteStandard_V2(parser_context_t* c, pd_AccountVoteSt
     return parser_ok;
 }
 
+parser_error_t _readCompactBountyIndex_V2(parser_context_t* c, pd_CompactBountyIndex_V2_t* v)
+{
+    return _readCompactInt(c, v);
+}
+
 parser_error_t _readAccountVote_V2(parser_context_t* c, pd_AccountVote_V2_t* v)
 {
     CHECK_INPUT()
@@ -1340,6 +1345,16 @@ parser_error_t _toStringLookupSource_V2(
     return parser_ok;
 }
 
+parser_error_t _toStringCompactBountyIndex_V2(
+    const pd_CompactBountyIndex_V2_t* v,
+    char* outValue,
+    uint16_t outValueLen,
+    uint8_t pageIdx,
+    uint8_t* pageCount)
+{
+    return _toStringCompactInt(v, 0, "", "", outValue, outValueLen, pageIdx, pageCount);
+}
+
 parser_error_t _toStringLeasePeriodOfT_V2(
     const pd_LeasePeriodOfT_V2_t* v,
     char* outValue,
diff --git a/app/src/substrate_types_V2.h b/app/src/substrate_types_V2.h
index 4a6933e..6eae2c3 100644
--- a/app/src/substrate_types_V2.h
+++ b/app/src/substrate_types_V2.h
@@ -30,6 +30,8 @@ typedef struct {
     const uint8_t* _ptr;
 } pd_AccountId_V2_t;
 
+typedef compactInt_t pd_CompactBountyIndex_V2_t;
+
 typedef struct {
     uint8_t value;
     union {