Any way to get an old Instagram account back if you have no access to the email but know the password?

So I have had an Instagram account for 4 years now. I haven’t used it since July 2015 and would really wish to delete it now or at least get it back.

I know the password, I entered it and it was correct but it said ‘suspicious login’, then I tried logging into my own email not expecting to know the email anymore and now I do know it, however I don’t know the password for that email so I clicked on ‘forgot password’. It asked me some basic questions which I obviously don’t remember as it was the device before my previous device.

Then it asked me when the account was created and I got it right, and it asked me to enter an email as they were going to be ‘reviewing the result’.

Shortly after it said that it could not sign me in. It’s very frustrating how Instagram doesn’t offer any help on this whatsoever so any help would be greatly appreciated, I mean it, this issue is urgent. If I cannot get over the suspicious login thing, can you at least tell me a way to login or delete the account? Thanks.

PS I know that this isn’t an Apple issue, but in a way it is because I used to have a device which hasn’t been backed up (in terms of Instagram data) so I cannot access my previous email and etc even if I know my password for the IG account.