diff --git a/src/composables/plotTemplates.ts b/src/composables/plotTemplates.ts
index cd2b6e82..9fecdb49 100644
--- a/src/composables/plotTemplates.ts
+++ b/src/composables/plotTemplates.ts
@@ -52,7 +52,9 @@ function replaceTemplateColumns(template: Partial<PlotConfig>, nameMap: Record<s
     const newKey = nameMap[key] || key;
     newMainPlot[newKey] = template.main_plot[key];
   }
-  newTemplate.main_plot = newMainPlot;
+  if ('main_plot' in template) {
+    newTemplate.main_plot = newMainPlot;
+  }
 
   // Replace the keys of all elements in subplots
   const newSubplots: Record<string, any> = {};
@@ -64,7 +66,9 @@ function replaceTemplateColumns(template: Partial<PlotConfig>, nameMap: Record<s
     }
     newSubplots[subplotKey] = newSubplot;
   }
-  newTemplate.subplots = newSubplots;
+  if ('subplots' in template) {
+    newTemplate.subplots = newSubplots;
+  }
   return newTemplate;
 }
 
@@ -90,6 +94,7 @@ export function usePlotTemplates() {
     plotTemplates,
     applyPlotTemplate,
     getTemplateContent,
+    replaceTemplateColumns,
     plotTemplateNames: computed(() => Object.keys(plotTemplates.value)),
   };
 }
diff --git a/tests/unit/plotTemplates.spec.ts b/tests/unit/plotTemplates.spec.ts
new file mode 100644
index 00000000..29a60900
--- /dev/null
+++ b/tests/unit/plotTemplates.spec.ts
@@ -0,0 +1,98 @@
+import { describe, it, expect } from 'vitest';
+
+import { usePlotTemplates } from '@/composables/plotTemplates';
+import { PlotConfig } from '@/types';
+
+describe('plotTemplates.ts', () => {
+  it('Updates main plot values', () => {
+    const { replaceTemplateColumns } = usePlotTemplates();
+    const reMapping = { ema: 'ema_14' };
+    const template: Partial<PlotConfig> = {
+      main_plot: {
+        ema: {
+          color: '#ff8000',
+          type: 'line',
+        },
+      },
+    };
+    const expected: Partial<PlotConfig> = {
+      main_plot: {
+        ema_14: {
+          color: '#ff8000',
+          type: 'line',
+        },
+      },
+    };
+    expect(replaceTemplateColumns(template, reMapping)).toEqual(expected);
+  });
+  it('Updates subplot plot values', () => {
+    const { replaceTemplateColumns } = usePlotTemplates();
+    const reMapping = { rsi: 'rsi_14' };
+    const template: Partial<PlotConfig> = {
+      subplots: {
+        RSI: {
+          rsi: {
+            color: '#ff8000',
+            type: 'line',
+          },
+        },
+      },
+    };
+    const expected: Partial<PlotConfig> = {
+      subplots: {
+        RSI: {
+          rsi_14: {
+            color: '#ff8000',
+            type: 'line',
+          },
+        },
+      },
+    };
+    expect(replaceTemplateColumns(template, reMapping)).toEqual(expected);
+  });
+  it('Updates both main and subplot values', () => {
+    const { replaceTemplateColumns } = usePlotTemplates();
+    const reMapping = { ema: 'ema_200', macd: 'macd_5m', macdsignal: 'macdsignal_5m' };
+    const template: Partial<PlotConfig> = {
+      main_plot: {
+        ema: {
+          color: '#ff8000',
+          type: 'line',
+        },
+      },
+      subplots: {
+        MACD: {
+          macdsignal: {
+            color: '#ff8000',
+            type: 'line',
+          },
+          macd: {
+            color: '#1370f4',
+            type: 'line',
+          },
+        },
+      },
+    };
+    const expected: Partial<PlotConfig> = {
+      main_plot: {
+        ema_200: {
+          color: '#ff8000',
+          type: 'line',
+        },
+      },
+      subplots: {
+        MACD: {
+          macdsignal_5m: {
+            color: '#ff8000',
+            type: 'line',
+          },
+          macd_5m: {
+            color: '#1370f4',
+            type: 'line',
+          },
+        },
+      },
+    };
+    expect(replaceTemplateColumns(template, reMapping)).toEqual(expected);
+  });
+});