REGAPP-43 git syntax wrong. Stopped working

.gitlab-ci.yml

@@ -27,6 +27,6 @@ build-job-schedule:
   script:
     - mkdir -p /kaniko/.docker
     - echo "{\"auths\":{\"$DOCKER_REGISTRY\":{\"auth\":\"$(echo -n ${DOCKER_REGISTRY_USER}:${DOCKER_REGISTRY_PASSWORD} | base64)\"}}}" > /kaniko/.docker/config.json
-    - /kaniko/executor --context $CI_PROJECT_DIR/reg-app --build-arg CHECKOUT_NAME=branch-2.7 --build-arg CHECKOUT_BRANCH_NAME=local_branch-2.7 --dockerfile $CI_PROJECT_DIR/reg-app/Dockerfile --destination $DOCKER_REGISTRY_NAME:2.7-nightly
+    - /kaniko/executor --context $CI_PROJECT_DIR/reg-app --build-arg CHECKOUT_NAME=origin/branch-2.7 --build-arg CHECKOUT_BRANCH_NAME=local_branch-2.7 --dockerfile $CI_PROJECT_DIR/reg-app/Dockerfile --destination $DOCKER_REGISTRY_NAME:2.7-nightly
   rules:
     - if: $CI_PIPELINE_SOURCE == "schedule"

reg-app/Dockerfile

@@ -5,7 +5,7 @@ ARG CHECKOUT_BRANCH_NAME=$CHECKOUT_BRANCH_NAME
 RUN git clone https://gitlab.kit.edu/kit/reg-app/regapp.git
 WORKDIR /app/regapp
 RUN git fetch --all
-RUN git checkout $CHECKOUT_NAME -b $CHECKOUT_BRANCH_NAME
+RUN git checkout -b $CHECKOUT_BRANCH_NAME $CHECKOUT_NAME
 
 FROM maven:3.6-openjdk-11-slim AS build