So,If I have a chance to meet you in HC company,I will hand over the air ticket to you in person,if not,I will hand it over to our accounting,and issue an invoice to you.
So, i will give you the ticket if i meet you in HC today. Or i will ask our Finance Department staff to invoice it to you. (基于你的要求用了invoice,但是这个词当动词时是开发票的意思,似乎跟你要表达的意思有些出入)
So, if I have the chance to meet you in HC, I'll bring the ticket to you. If not, I'll turn the ticket to our financial department and provide it to you by invoice.
So I will come to meet you in HC and give you the airline tickets if I get the chance. Otherwise I will give it to our finance staff and send the invoice to you.