diff --git a/src/addon/qtype/calculated/providers/handler.ts b/src/addon/qtype/calculated/providers/handler.ts
index 22423edb4..0e432658f 100644
--- a/src/addon/qtype/calculated/providers/handler.ts
+++ b/src/addon/qtype/calculated/providers/handler.ts
@@ -191,7 +191,7 @@ export class AddonQtypeCalculatedHandler implements CoreQuestionHandler {
         let unitsLeft = false;
         let match = null;
 
-        if (!question.settings) {
+        if (!question.settings || question.settings.unitsleft === null) {
             // We don't know if units should be before or after so we check both.
             match = answer.match(new RegExp('^' + regexString));
             if (!match) {
diff --git a/src/core/question/classes/base-question-component.ts b/src/core/question/classes/base-question-component.ts
index 91a238153..0dbd9df63 100644
--- a/src/core/question/classes/base-question-component.ts
+++ b/src/core/question/classes/base-question-component.ts
@@ -108,7 +108,7 @@ export class CoreQuestionBaseComponent {
                 this.question.select = selectModel;
 
                 // Check which one should be displayed first: the select or the input.
-                if (this.question.settings) {
+                if (this.question.settings && this.question.settings.unitsleft !== null) {
                     this.question.selectFirst = this.question.settings.unitsleft == '1';
                 } else {
                     const input = questionEl.querySelector('input[type="text"][name*=answer]');
@@ -166,7 +166,7 @@ export class CoreQuestionBaseComponent {
             }
 
             // Check which one should be displayed first: the options or the input.
-            if (this.question.settings) {
+            if (this.question.settings && this.question.settings.unitsleft !== null) {
                 this.question.optionsFirst = this.question.settings.unitsleft == '1';
             } else {
                 const input = questionEl.querySelector('input[type="text"][name*=answer]');