I have finally received a response from Blockchain:

 
I appreciate your patience while waiting for a response.
 
I apologize for any inconvenience caused by the delay in resolving your issue. In order to assist you further, could you please provide additional information?
 
Could you kindly share the following details with us:
 
SMS Number
2FA type used (SMS, Email, None)
Last Date Accessed
Creation IP address
 
Upon receiving this information, we will be able to investigate the matter in our system. Thank you for your understanding and cooperation.
 
Warm regards,
 
Zee | Blockchain.com Support


So it seems I have a fresh attempt of trying to deal with them.