Complaint sub-issue: Company closed your account

I opened a checking 's account with Discover Bank in order to use their 1 % back debit card. That card was activated on the XXXX of XXXX. Since Discover Bank is entirely virtual with no physical banking locations, I would have to deposit checks, wire money, or so forth virtually in order to submit funds to the account. On XX/XX/XXXX I deposited a cashiers check for the amount of {$5900.00} plus a {$10.00} fee for the cashiers check, totaling {$5900.00} being removed from my XXXX bank account, and {$5800.00} being deposited into my Discover Bank account. The following morning I saw that the cashiers check had cleared pending charges and was in the account, although I did not attempt to use any of it incase it was still not entirely available yet ( the Discover Bank app makes it confusing to know if the funds are entirely available or not yet ). Later that day on the XXXX I received an email from Discover Bank saying " we noticed unusual activity on your account. For security purposes, we have suspended access to your account. If you have already spoken to us about this, no further action is needed. '' I immediately called them with quite distress as practically every dollar I own as a college student was supposed to be deposited into that account. Upon calling them an automated message told me they closed my account upon suspicious activity and no longer would like to do business with me. It continued to say my funds would be held for up to 60 days which is when a check would be written and sent back to me. I tried to connect to an agent who was extremely kind, but offered no real help as she could not find out any additional information. By this time I had merged my father into the call as I was panicking and couldn't think clearly myself. We ended up speaking to a manager who claimed to of escalated the complaint and said that he would reach out to the department that closed the account and try to find answers, giving me a call back by Monday the XXXX of XXXX at the latest. Monday comes around and I have not received a call. I gave the manager until Tuesday the XXXX of XXXX just in case, but still as of today, the XXXX of XXXX I have heard nothing back. At this point, I have tried to be patient and kind to Discover Bank, asking and waiting patiently to speak to someone who may know something about the account closure, offering to even provide proof that the funds were 100 % real and in no part fraud, but they have evidently not cared enough to reach back out. I am confused how not only can a bank be so careless about an individuals funds ( especially when those funds were supposed to be directed towards paying my share of rent to keep a roof over my head for the next 5 months ), but also how they can hold money without no proof or willingness to be provided proof for up to 60 days? Is 60 days considered " a reasonable amount of time '' as coined by the FDIC? I will be providing a screenshot of the statement from XXXX bank proving the funds came from my account and were verified by XXXX. Please note, I would provide the account number if I could, although I never received an account statement and can not access the online account to find it. If there are any other questions, please let me know.