Traefik : Let's Encrypt + other certificate - ssl

Question

I have 3 nodes swarm and I wish to use TRAEFIK with Let'sEncryp and my own certificates generated by the company www.tbs-internet.com. Is it possible? Currently it works with Let's Encrypt but not with my other certificates.
With the configuration files, I have the following error in the logs of Traefik:
time="2017-07-05T12:07:57Z" level=info msg="Preparing server http &{Network: Address::80 TLS:<nil> Redirect:<nil> Auth:0xc420339360 Compress:false}"
time="2017-07-05T12:07:57Z" level=info msg="Preparing server https &{Network: Address::443 TLS:0xc4204fe600 Redirect:<nil> Auth:0xc4203396c0 Compress:false}"
time="2017-07-05T12:07:57Z" level=info msg="Starting server on :80"
time="2017-07-05T12:07:57Z" level=error msg="Error creating TLS config: tls: failed to parse private key"
time="2017-07-05T12:07:57Z" level=fatal msg="Error preparing server: tls: failed to parse private key"
traefik.toml
defaultEntryPoints = ["http", "https"]
[entryPoints]
[entryPoints.http]
address = ":80"
[entryPoints.https]
address = ":443"
[entryPoints.https.tls]
[[entryPoints.https.tls.certificates]]
CertFile = "/tls/fs/preprod.appx.mydomainA.com.cert"
KeyFile = "/tls/fs/preprod.appx.mydomainA.com.key"
[acme]
email = "xxxxxxxxxxxxxxxxxxx"
storage = "acme.json"
entryPoint = "https"
onDemand = true
[[acme.domains]]
main = "admin.mydomainC.com"
[web]
address = ":8080"
docker-compose.yml for Traefik
version: '3'
services:
proxy-prod:
image: traefik:v1.3.1-alpine
command: --web --docker --docker.swarmmode --docker.domain=traefik.admin.mydomainC.com --docker.watch --logLevel=DEBUG
networks:
- net-prod
ports:
- "80:80"
- "443:443"
- "8080:8080"
volumes:
- /var/run/docker.sock:/var/run/docker.sock
- $PWD/traefik.toml:/traefik.toml
- "/home/swarm/ssl:/tls"
deploy:
mode: global
networks:
net-prod:
driver: overlay
external:
name: net-prod
docker-compose.yml for app1
version: '3'
networks:
net-prod:
driver: overlay
external:
name: net-prod
services:
app1:
image: private/app1
networks:
- net-prod
deploy:
labels:
- "traefik.backend=app1"
- "traefik.frontend.rule=Host:app1.app.mydomainC.com,preprod.appx.mydomainA.com"
- "traefik.docker.network=net-prod"
- "traefik.port=9001"
replicas: 1
Do you have an idea ?
The app1 service have two URLs :
app1.app.mydomainC.com : with Let's Encrypt
preprod.appx.mydomainA.com : my own certificates generated by the company www.tbs-internet.com