No mobile data in Europe

[BBC]

Hi,

arrived in Denmark 2 days ago and have no mobile data. Have call customer service  and advised to reset network settings with no luck. The call got disconnected and I have got network provider voicemail which I can’t access or call back. When I try to call O2 customer s back after 24 hours I still get the message that they know I have called and they will call me back followed by a disconnection. No attempt have been made to call me back in the last 24 hours or if they have it is not getting through. Is there any other way to contact customer service to solve this problem? 

[MI5]

@BBC 

Some things to try:
Check data roaming is on in phone settings.
Manually search for another network
Turn off 5g
Change your data APN to "mobile.o2.co.uk"
Check with O2 whether you have a roaming bar on your account. Do this via social media
If you message O2 on Facebook ( https://o2uk.co/O2CFB) , Twitter ( https://o2uk.co/O2CTW) or Instagram ( https://o2uk.co/O2CIG) , they should be able to help.

Guide: How to find help & contact O2