high tulip
When trying to give Frank and Zarah gifts for their birthday, there is no option to give them a second. This also occurs with other characters, such as Eva and Luke. I had given Frank one gift earlier that week, but I hadn't gifted Zarah anything before the 16th.
On the 15th of Summer (One day before Frank and Zarah's birthday) I gave Frank a larkspur. However, I did not gift anything to Zarah on that day.
On the 16th (Frank and Zarah's birthday), I gifted Zarah a larkspur, and when I tried to give her another one, there was no option to. Then I went and gifted Frank a larkspur as well, and the same issue occurred.
As displayed in the video I've attached, I tried to walk away from them, I tried to enter and leave a building before trying again, and tried gifting another item, but none of these fixed the issue.
In-game date: Summer 16 (Zarah and Frank's birthday)
Game platform: Steam (PC), Keyboard/Mouse
Game version: v1.1b-1237
I've also attached my save file. If any additional information is needed, please let me know! Hope this helps 
~~Also apologies for the messy handwriting lol! 
~~
