diff --git a/packages/devices/src/drivers/printer-escpos.ts b/packages/devices/src/drivers/printer-escpos.ts
index 76cfd8c..7a1f000 100644
--- a/packages/devices/src/drivers/printer-escpos.ts
+++ b/packages/devices/src/drivers/printer-escpos.ts
@@ -119,13 +119,20 @@ function line(text = ""): Buffer {
 // dependency). The same code is printed as large human-readable digits below, so
 // the operator can hand-key it if every reader fails.
 
-/** GS k — Code128 1D barcode. Height/width set first, then HRI off, then data. */
-function code128(data: string): Buffer {
+/** GS k — Code128 1D barcode. Height/width set first, then HRI off, then data.
+ *  `moduleWidth` (narrow-bar dots, 1–6) trades scan-tolerance for total width: at ~11
+ *  modules/char a 13-char id fits 80mm (576 printable dots) at width 3, but a ~20-char
+ *  id needs width 2 or it OVERFLOWS the head and the firmware silently aborts the
+ *  barcode (prints nothing). Keep the symbol LEFT-aligned — centering shifts the start
+ *  point right and makes a wide barcode overflow even sooner. */
+function code128(data: string, moduleWidth = 3): Buffer {
   // Code128 code set B (printable ASCII) — prefix the data with the {B selector.
   const payload = Buffer.from(`{B${data}`, "ascii");
+  const w = Math.max(1, Math.min(6, moduleWidth));
   return Buffer.concat([
+    ALIGN_LEFT, // a wide barcode must start at the left margin to fit the 80mm head
     Buffer.from([GS, 0x68, 0x64]), // GS h 100 — barcode height = 100 dots (taller = tolerant of scan angle)
-    Buffer.from([GS, 0x77, 0x03]), // GS w 3  — module width = 3 (wider bars for the short-range "Simple" QR/barcode engine; 13-digit Code128 ≈ 495/576 dots, fits 80mm with quiet zones)
+    Buffer.from([GS, 0x77, w]), // GS w n — module (narrow-bar) width in dots
     Buffer.from([GS, 0x48, 0x00]), // GS H 0  — HRI text off (we print the id ourselves)
     // GS k 73 n <data>  — function B form: 73 = Code128, n = data byte length.
     Buffer.from([GS, 0x6b, 0x49, payload.length]),
@@ -418,9 +425,12 @@ export function renderReceipt(data: ReceiptData): Buffer {
   ];
 
   if (data.voucher) {
-    // The same ticket id, scannable at the exit reader, + the grace emphasis.
+    // The same ticket id, scannable at the exit reader, + the grace emphasis. code128
+    // forces ALIGN_LEFT (a wide barcode must hug the margin); restore centering for the
+    // human-readable id + grace lines that follow.
     parts.push(
       code128(data.ticketId),
+      ALIGN_CENTER,
       line(),
       line(data.ticketId),
       line(),
@@ -456,10 +466,14 @@ export function renderWindowChargeNotice(data: WindowChargeNoticeData): Buffer {
     line(STR.windowTitle),
     BOLD_OFF,
     line(),
-    // The occurrence id, scannable two ways: Code128 for a 1D laser scanner, QR for
-    // the booth's combo reader. Either pulls the occurrence up in the pay modal.
-    code128(data.occurrenceId),
+    // The occurrence id, scannable two ways. Code128 for a 1D laser scanner FIRST —
+    // module width 2 + left-aligned (code128 forces ALIGN_LEFT) because the ~20-char
+    // occurrence id is too wide to fit the 80mm head at width 3 (the firmware would
+    // abort it). Then the QR for the booth's combo reader. Either pulls the occurrence
+    // up in the pay modal.
+    code128(data.occurrenceId, 2),
     line(),
+    ALIGN_CENTER,
     qrCode(data.occurrenceId),
     line(),
     // The id in text, as the hand-key fallback if neither scans.