diff --git a/llmage/accounting.py b/llmage/accounting.py
index 57fce5a..4cb351c 100644
--- a/llmage/accounting.py
+++ b/llmage/accounting.py
@@ -172,7 +172,7 @@ where a.llmid = b.id
 				if len(io['output']) == 0:
 					llmusage.accounting_status = 'failed'
 					await sor.U('llmusage', {'id': llmusage.id, 'accounting_status': 'failed'})
-					debug(f'{len(io['output'])} is 0')
+					debug(f'{len(io["output"])} is 0')
 					continue
 				r.usages = io['output'][-1]['usage']
 			if r.usages is None: