diff --git a/packages/backend/src/database/schemas/purchase.schema.ts b/packages/backend/src/database/schemas/purchase.schema.ts
index 4c7e017..b047356 100644
--- a/packages/backend/src/database/schemas/purchase.schema.ts
+++ b/packages/backend/src/database/schemas/purchase.schema.ts
@@ -40,6 +40,7 @@ export class Purchase {
     assetName?: string;
     industry?: string;
     riskTier?: string;
+    type?: 'PURCHASE' | 'DEPOSIT'; // Track if this is a purchase or deposit
   };
 
   // Timestamps (automatically added by Mongoose with timestamps: true)
diff --git a/packages/backend/src/modules/marketplace/dto/notify-purchase.dto.ts b/packages/backend/src/modules/marketplace/dto/notify-purchase.dto.ts
index 66490f2..f68edef 100644
--- a/packages/backend/src/modules/marketplace/dto/notify-purchase.dto.ts
+++ b/packages/backend/src/modules/marketplace/dto/notify-purchase.dto.ts
@@ -1,4 +1,4 @@
-import { IsString, IsNotEmpty, IsNumberString, IsOptional } from 'class-validator';
+import { IsString, IsNotEmpty, IsNumberString, IsOptional, Matches } from 'class-validator';
 
 export class NotifyPurchaseDto {
   @IsString()
@@ -9,9 +9,9 @@ export class NotifyPurchaseDto {
   @IsNotEmpty()
   assetId!: string;
 
-  @IsNumberString()
+  @Matches(/^-?\d+$/, { message: 'amount must be a valid number string (can be negative)' })
   @IsNotEmpty()
-  amount!: string; // Token amount purchased (in wei)
+  amount!: string; // Token amount purchased (in wei) - can be negative
 
   @IsOptional()
   @IsNumberString()
diff --git a/packages/backend/src/modules/marketplace/services/purchase-tracker.service.ts b/packages/backend/src/modules/marketplace/services/purchase-tracker.service.ts
index fb465bc..cc313d1 100644
--- a/packages/backend/src/modules/marketplace/services/purchase-tracker.service.ts
+++ b/packages/backend/src/modules/marketplace/services/purchase-tracker.service.ts
@@ -81,6 +81,8 @@ export class PurchaseTrackerService {
         assetName: `${asset.metadata?.invoiceNumber} - ${asset.metadata?.buyerName}`,
         industry: asset.metadata?.industry,
         riskTier: asset.metadata?.riskTier,
+                          type: 'PURCHASE', // Mark as purchase
+
       },
     });
 
diff --git a/packages/backend/src/modules/solvency/controllers/solvency.controller.ts b/packages/backend/src/modules/solvency/controllers/solvency.controller.ts
index 0aba9ce..e3c2ce2 100644
--- a/packages/backend/src/modules/solvency/controllers/solvency.controller.ts
+++ b/packages/backend/src/modules/solvency/controllers/solvency.controller.ts
@@ -244,15 +244,15 @@ export class SolvencyController {
       throw new BadRequestException('Position does not belong to authenticated user');
     }
 
-    // Auto-detect token type based on Asset collection
-    const tokenType = await this.positionService.determineTokenType(positionData.collateralToken);
+    // Use token type directly from blockchain (0 = RWA, 1 = PRIVATE_ASSET)
+    const tokenType = positionData.tokenType === 0 ? 'RWA' : 'PRIVATE_ASSET';
 
     // Sync database record (update if exists, create if not)
     const position = await this.positionService.syncPosition(
       positionId,
       positionData.user,
       positionData.collateralToken,
-      tokenType,
+      tokenType as any,
       positionData.collateralAmount.toString(),
       positionData.tokenValueUSD.toString(),
       dto.txHash,
diff --git a/packages/backend/src/modules/solvency/services/solvency-blockchain.service.ts b/packages/backend/src/modules/solvency/services/solvency-blockchain.service.ts
index 8dc3dc3..af663bd 100644
--- a/packages/backend/src/modules/solvency/services/solvency-blockchain.service.ts
+++ b/packages/backend/src/modules/solvency/services/solvency-blockchain.service.ts
@@ -154,6 +154,8 @@ export class SolvencyBlockchainService {
     usdcBorrowed: bigint;
     tokenValueUSD: bigint;
     createdAt: bigint;
+    liquidatedAt: bigint;
+    creditLineId: bigint;
     active: boolean;
     tokenType: number;
   }> {
@@ -169,6 +171,17 @@ export class SolvencyBlockchainService {
       args: [BigInt(positionId)],
     }) as any;
 
+    this.logger.log(`Position user retrieved for ID ${position[0]}`);
+    this.logger.log(`Position collateral token: ${position[1]}`);
+    this.logger.log(`Position collateral amount: ${position[2]}`);
+    this.logger.log(`Position USDC borrowed: ${position[3]}`);
+    this.logger.log(`Position token value USD: ${position[4]}`);
+    this.logger.log(`Position created at: ${position[5]}`);
+    this.logger.log(`Position liquidated at: ${position[6]}`);
+    this.logger.log(`Position credit line ID: ${position[7]}`);
+    this.logger.log(`Position active: ${position[8]}`);
+    this.logger.log(`Position token type: ${position[9]}`);
+
     return {
       user: position[0],
       collateralToken: position[1],
@@ -176,8 +189,10 @@ export class SolvencyBlockchainService {
       usdcBorrowed: position[3],
       tokenValueUSD: position[4],
       createdAt: position[5],
-      active: position[6],
-      tokenType: position[7],
+      liquidatedAt: position[6],
+      creditLineId: position[7],
+      active: position[8],
+      tokenType: position[9],
     };
   }