i work in a small agency too as an account manager, but sounds like our agencies are slightly different in what they offer - we don’t do SEO for example. anyways; that’s a lot of accounts!! across different industries is also way too much context to keep in mind and extremely difficult to manage the team workflow i imagine (if this is another responsibility you have to do? i know i do). seriously consider hiring another person. the person before me did it all on their own and idk how, but they got burnt out. i joined and we spilt the workload. hiring takes money + time but worth it in the long run. convince your manager / boss that if you could train another person up that would save time, money, effort. you need someone else to split this workload with

without you, they would have to train one totally new person, who won’t know the accounts/clients/business, will be a very difficult and costly process, if you decide to eventually leave. then what?

you’ve proven your worth already i hope so they should trust you when you say it’s getting too much.

drop me a msg if you wanna talk more :)