Product: Checking or savings account

I am a XXXX citizen and I have been a loyal customer of Citibank since XXXX. Over those XXXX years, I never gave any problems. I have a simple package of current & saving accounts ( one individual account, and one with my husband ), plus CDAs from time to time. I am writing because Citibank has blocked my account and a flaw in their process is preventing me from unblocking it. 
I moved from the XXXX to XXXX in XXXX. I updated my contact information with Citibank, and they have on their records XXXX XXXX  mailing addresses ( in one of them I have received there countless letters in these almost XXXX  years, latest one in XXXX this year ). Citibank also has on their systems a XXXX  mobile number and a XXXX  mobile number, both still valid and where I have received automated SMS from Citibank systems ( latest one in XX/XX/XXXX ). 
In XX/XX/XXXX, I visited friends in XXXX. It was the first time I was in the XXXX since before the pandemic. I visited a Citibank branch to open two CDAs, and make some updates to my account, as per the bank clerk recommendation. He suggested I upgraded to Citi Priority. During the change in the account package, I gave a second XXXX  email address. The clerk told me I had to give a XXXX number ( they will never use it, they said ) so I gave my friends mobile number. 
Because my debit card was expiring this XXXX, I requested a new debit card at the branch, and used it for the first time in 3 years ( to get some cash, pay in two restaurants and in one souvenir shop ). I guess this activity may have looked suspicious to Citibank and they blocked my account. I was only in the XXXX between XX/XX/XXXX and XX/XX/XXXX. When I was back in XXXX, I received an email to call their Fraud prevention line to fix the issue. I promptly did the same day I got the email ( XX/XX/XXXX ). The person on the line told me that the only way to unblock my account was if I called them from a verified XXXX number. I explained to her that I do not own a XXXX number for XXXX years and that they have both my XXXX  and my XXXX  numbers on their systems. But they do not accept international numbers for verification. I also told her my friends phone number but she said that was not the right one. 
Right before hanging up on me, the fraud department employee said that a letter with a reference number would be sent to my address on record, and that I could call with that number to unfreeze the account. 
Citibank has also blocked my online access to my accounts, I can not use my registered email/password to see balances or movements or to make any operations ( with neither my individual account or my joint account, which is not blocked ).

Over two weeks passed and the letter did not arrive ( another letter for a separate topic did arrive, proving once more that they have my XXXX  address correctly registered ). On XX/XX/XXXX, I called again the Citibank Fraud department. The person on the phone this time told me there was no record of a letter being sent to my mailing address and that the only way to unblock my account was if I called them from a XXXX verified number, and she refused to pass me to a supervisor and proceed to hang up on me. Again, this person tried my XXXX  and XXXX  numbers and said they were not valid to verify my identity. I tried calling XXXX Customer Service. The person that attended me, XXXX, was very kind, and explained that only one of my accounts ( the main one, for which I am the only signer ) is blocked and passed me with her supervisor XXXX, who then pass me with the Fraud department ( XXXX XXXX, who then passed me with a Fraud supervisor called XXXX. She promised me she will send me a letter with a reference number to my XXXX  mailing address and that I should receive it in 7-10 days.

The balances in my blocked accounts are : savings : {$1900.00}, checking : {$2100.00}. Im attaching the emails with the weekly balances I still receive. My third account, with a balance of {$2000.00} is not blocked. 
Additionally, I have {$70000.00} in CDAs that will expire in XX/XX/XXXX and that are linked to my main ( blocked ) account. Im attaching the document from Citi branch listing the CDAs I opened. 
I called again the Fraud department on XX/XX/XXXX. The person who attended my call, XXXX, could not confirm whether a letter was sent out or not. I asked to speak to a supervisor, who told me the only way to verify my identity was to call from a verified XXXX number. Then, she proceeded to hang up on me. 
I also wrote the branch clerk. He said he will look into it, but no resolution yet. 
Citibank Fraud department wont accept any other ways of verification. I have two security questions, a security number, I offered to send them my passport, my SS card, tell them the balance in the accounts. They wont even tell me if going to a physical branch could help. 
On XX/XX/XXXX I called the Citibank Customer Service number, this time the person on the phone, XXXX, said he couldn't help me, only the Fraud department can unblock my account. He did not offer any information as to how long the account will remain blocked, if I will lose all the money there, what would be the next steps. Nothing, total black box.

No one at Citibank told me when I moved overseas that I would need to keep a XXXX number for verification purposes. I am now in an impossible situation, unable to unblock my account and have access to my own money. 
I am attaching the following documentation : Document from Citi branch listing the CDAs I opened, which shows the new XXXX  address I gave ( XXXX XXXX XXXX XXXX  XXXX ) Form 1099 sent this year for my XXXX taxes, indicating my old XXXX  address ( XXXX XXXX XXXX XXXX ) Citibank email indicating my account was blocked Emails indicating the balance of my accounts ( checking & Savings ) this week and also the balance at the beginning of XXXX, to show that there the balance in the accounts have not changed much ( only the XXXX XXXXXXXX for the CDAs ). It is not like there were crazy charges or anything.