WHMCS waiting for a process to finish before starting another

[darkkean]

I have read a forum post here which seems to be very similar to my problem right now. I chose not to reply to the said thread because it's too old (2007).

 

This is my problem:

1. I open two browser tabs in Chrome

2. First tab - I am sending mass email to 312 accounts which are divided to 13 steps

3. Step 1 is loading....

4. I continued working on Second tab - replying to a ticket.

5. On this second tab, I noticed it's only loading... like the first tab.

6. Tab 1 stopped loading. Step 1 of 13 is finished. Please wait...

7. Tab 2 loaded. My ticket reply was added.

8. Tab 1 is loading again, process Step 2 of 13. Please wait...

9. I clicked a link on Tab 2 and it is loading too. Seems like waiting for Tab 1 to finish.

10. And the same goes on....

 

My WHMCS v7.0 is installed on a Vultr box Ubuntu 14, PHP 5.6 and using Serverpilot.

 

What should I do? I want WHMCS to do things simultaneously and "not wait" for the other process to finish before continuing.

 

Please help. Thank you!