use id in format

synced-pool.go

@@ -471,8 +471,7 @@ func (p *SyncedPool) getGrainPool(id CartId) (GrainPool, error) {
 				p.mu.Lock()
 				delete(p.remoteIndex, id)
 				p.mu.Unlock()
-				return nil, fmt.Errorf("remote pool is nil", id)
-
+				return nil, fmt.Errorf("remote pool is nil for %v", id)
 			}
 			remoteLookupCount.Inc()
 			return remotePool, nil