Manually trigger hook

[berstein]

Hello all,

I was wondering if is there any way I can manually trigger a hook?
I'm currently using custom module and also paid module (encrypted) and they kinda won't work together.
What I need is to trigger the paid module's hook function (I assume it use UpdateInvoiceTotal hook) after my custom module done executing.
My custom module use UpdateInvoice API, but it wont trigger the UpdateInvoiceTotal hook.

Any advice is welcomed.
Thank you