Re-create account after expiration

Hello. My account expired once. So I re-created a new account, but it says it has already expired. I have given the same email address. Is this the reason?
Then, how can I reactivate my account once it has expired? I would appreciate it if you could tell me.
Thank you so much in advance.

Y. S.

Individual user can only create one 30-days trial.
Afterwards you can upgrade to one of the paid plans. I would also recommend to check options for ESA-sponsored access:

Thank you so much for your prompt reply.
I should consider upgrading my account.

Thank you so much!