diff --git a/obp-api/src/main/scala/code/api/util/APIUtil.scala b/obp-api/src/main/scala/code/api/util/APIUtil.scala
index 925fcfdc14..7e6bbc17ff 100644
--- a/obp-api/src/main/scala/code/api/util/APIUtil.scala
+++ b/obp-api/src/main/scala/code/api/util/APIUtil.scala
@@ -3148,7 +3148,13 @@ object APIUtil extends MdcLoggable with CustomJsonFormats{
         val message = ErrorMessages.InvalidConsentIdUsage
         Future { (fullBoxOrException(Empty ~> APIFailureNewStyle(message, 400, Some(cc.toLight))), Some(cc)) }
       } else if (APIUtil.`hasConsent-ID`(reqHeaders)) { // Berlin Group's Consent
-        Consent.applyBerlinGroupRules(APIUtil.`getConsent-ID`(reqHeaders), cc.copy(consumer = consumerByCertificate))
+        // Choose consumer based on validation method configuration
+        val consumerForConsent = if (method == "CONSUMER_KEY_VALUE" && consumerByConsumerKey.isDefined) {
+          consumerByConsumerKey
+        } else {
+          consumerByCertificate
+        }
+        Consent.applyBerlinGroupRules(APIUtil.`getConsent-ID`(reqHeaders), cc.copy(consumer = consumerForConsent))
       } else if (APIUtil.hasConsentJWT(reqHeaders)) { // Open Bank Project's Consent
         val consentValue = APIUtil.getConsentJWT(reqHeaders)
         Consent.getConsentJwtValueByConsentId(consentValue.getOrElse("")) match {
diff --git a/obp-api/src/main/scala/code/api/util/ConsentUtil.scala b/obp-api/src/main/scala/code/api/util/ConsentUtil.scala
index 45358d0289..40ab6630ce 100644
--- a/obp-api/src/main/scala/code/api/util/ConsentUtil.scala
+++ b/obp-api/src/main/scala/code/api/util/ConsentUtil.scala
@@ -255,7 +255,12 @@ object Consent extends MdcLoggable {
           if(requestConsumerId == "NONE" || consumerValidationMethodForConsent.isEmpty) {
             logger.warn(s"consumer_validation_method_for_consent is empty while request consumer_id=NONE - consent_id=${consent.jti}, aud=${consent.aud}")
           }
+          // Get consumer keys for debugging
+          val consentConsumerKey = Consumers.consumers.vend.getConsumerByConsumerId(consentConsumerId).map(_.key.get).getOrElse("Unknown")
+          val requestConsumerKey = callContext.consumer.map(_.key.get).getOrElse("None")
+          val detailedErrorMsg = s"${ErrorMessages.ConsentNotFound} Consumer mismatch: consent has consumer_id='$consentConsumerId' (consumer_key='$consentConsumerKey'), but current request has consumer_id='$requestConsumerId' (consumer_key='$requestConsumerKey')"
           logger.debug(s"ConsentNotFound: TPP/Consumer mismatch. Consent holder consumer_id=$consentConsumerId, Request consumer_id=$requestConsumerId, consent_id=${consent.jti}")
+          logger.debug(s"ConsentNotFound: $detailedErrorMsg")
           ErrorUtil.apiFailureToBox(ErrorMessages.ConsentNotFound, 401)(Some(callContext))
         } else if (!verifyHmacSignedJwt(consentIdAsJwt, c)) { // verify signature
           Failure(ErrorMessages.ConsentVerificationIssue)