Strange calls from 2 different o2 Kundenbetreuung.

Recently I received a call from +49 176 88840216 named O2 Kundenbetreuung. I picked it up, asked in Germany if the caller also spoke English, which they informed me they do not and asked me to wait for them to get someone who does.

After being put on hold the call hung up after 10 seconds and I did not receive a call back.

Now after a few days I received another call from O2 Kundenbetreuung but from the number +49 176 88840224.

Are these official O2 numbers or is something wrong here? I don't wish to call back in case of a potential Click Call scam so I want to verify before hand.