H3G suspected fraud on my account

R1skymndy

I have recently found that H3G have set up possibly 3 counts on my late husbands bank account.  They have closed 2 but now will not talk to me.  I have a contract coming to a close in a couple of days but will not stay with them now.  The accounts were opened at a time that my husband was very ill in hospital so there is no way he could have possibly opened them.  These have been opened by 3 for a member of their staff. 
What is the best way to take this forward. I see that this was an issue in the past with H3G

Hasbeen

Sorry for your loss.

There have been various scams regards providers like 3 as below:

https://www.techradar.com/uk/news/three-mobile-customers-targeted-by-phishing-attack-heres-what-you-need-to-know

But you are saying 3 themselves opened the accounts for their staff members and you were paying for them?