[Bug] Claude Code fails to apply file edits, posts REPLACE block instead

Bug Description
its not applying edits nor is it following instructions, when i tell him he didnt apply his fixes. instead he posts the whole edit in the chat with REPLACE
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Environment Info

• Platform: win32
• Terminal: vscode
• Version: 2.0.14
• Feedback ID: d59fc571-0e57-459e-85d0-552f36b7d554

Errors

[{"error":"Error: Language not supported while highlighting code, falling back to markdown: undefined\n    at hK (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:729)\n    at file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:457\n    at Array.map (<anonymous>)\n    at tF (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:448)\n    at OlB (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:12745)\n    at G$ (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:73:19415)\n    at ka (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:42814)\n    at S9 (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:38355)\n    at Wm (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:38283)\n    at z$ (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:38137)","timestamp":"2025-10-14T13:19:15.485Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: undefined\n    at hK (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:729)\n    at file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:457\n    at Array.map (<anonymous>)\n    at tF (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:448)\n    at OlB (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:12745)\n    at G$ (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:73:19415)\n    at ka (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:42814)\n    at S9 (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:38355)\n    at Wm (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:38283)\n    at z$ (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:38137)","timestamp":"2025-10-14T13:19:15.488Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: undefined\n    at hK (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:729)\n    at file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:457\n    at Array.map (<anonymous>)\n    at tF (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:448)\n    at OlB (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:12745)\n    at G$ (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:73:19415)\n    at ka (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:42814)\n    at S9 (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:38355)\n    at Wm (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:38283)\n    at z$ (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:38137)","timestamp":"2025-10-14T13:19:15.492Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: undefined\n    at hK (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:729)\n    at file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:457\n    at Array.map (<anonymous>)\n    at tF (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:448)\n    at OlB (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2123:12745)\n    at G$ (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:73:19415)\n    at ka (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:42814)\n    at S9 (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:38355)\n    at Wm (file:///C:/Users/rer/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:75:38283)\n    at z$ (file:///C:/Users/rer/AppData/Roaming/npm/

Note: Error logs were truncated.