if($smerit+$source < $merits && $ID_MEMBER!=35)
fatal_error("You do not have enough sendable merit.", false);
I guess the merit economy needed some emergency repo operations.

@theymos: It looks like your "emergency update" broke things:
Did anybody face any problem with merit that send by theymos for the 10th-anniversary contest? I have faced some problem when theymos sent me merits for second time that, I see, I received some merits in my merit history but when I click on the link of which post merited, But I can not find any merit on the post that send by theymos. I have also checked others' profiles for making me sure. But I also faced the same problem/error on others' profiles too.
The user above has received this from you:
Today at 04:25:17 AM: 3 from theymos for Re: 10th anniversary art contest
Today at 02:04:18 AM: 10 from theymos for Re: 10th anniversary art contest
November 18, 2019, 08:53:04 PM: 50 from theymos for Re: 10th anniversary art contest
These are the posts:
50 Merit,
no Merit (instead of 10) from you, and
3 Merit from you again.
Update: it looks like it's fixed now.