Bug/Issue Can't propose marriage

I'm having an issue where I'm trying to give Harvey the Mermaid's Pendant. We're at 10 hearts and I've given him a bouquet. I've also seen all of his heart events. For some reason he's listed as single in the friendship log which he wasn't before and I'm not sure if this is because I waited too long or what exactly is going on (I gave him the bouquet in fall year 1 and it is now the last day of fall year 2). Every time I give him the pendant it glitches onto the ground behind him and he doesn't react. I cannot pick it up after this. I've tried giving him more bouquets so he's not listed as single but nothing seems to be working. Please help

 

I'm having the exact same problem. It's only been one season since I gave him the bouquet (and the bouquet icon shows up next to his name in the friendship log), but every attempt to gift the mermaid pendant just throws it on the ground.

 

I've been trying to give him gifts/bouquets as often as I can but nothing seems able to remove the single tag

 

I tried giving Harvey the pendant while he was outside and it actually worked! It's not really a fix imo but I did manage to get around the problem. Thanks to Chronos on the Steam forums who suggested I try that