I am using zoho for a while for now. now one of my senior's mail id is blocked due to space( she used her free space of 5gb upto 102 % now). No incoming and outgoing emails

We have deleting older messages more than 200of it for creating space. but it's still blocked and shows 102% of 5gb. We can't delete some of the recent emails because it contains important docs. Exporting emails also failed because download file mail is not getting.

Please help me with this. this is kinda urgent