Pure Scents Bath & Body

Hi all, I'm hoping someone can help me as I've been searching for weeks and can't seem to find the answer I'm looking for? All the products I ship out are holding up fine in the summer heat, with the exception of my emulsified sugar scrubs. I've recently reformulated my recipe to increase it's melting point, and I'm still having issues. The glass jars are leaking during transit! I prefer glass over plastic, and already have all the jars so I'm REALLY trying to work with what I have rather than order different jars. The lids have a silicone seal, and seem to close securely in my opinion. I've tried putting saran wrap under the lid, sealing it, then wrapping the whole jar in bubble wrap. I'm already using an ice pack, which is obviously not lasting long enough since customers are saying the ice pack is completely warm on arrival. I'm hesitant to keep tweaking my recipe and now looking at different packaging options. I'm fine with the scrub arriving soft, since I include a printed card that explains that the customer should place the product in the fridge for a little while before opening if necessary. But I'm NOT ok with the leaking! (Obviously..lol). I'm looking for the best way to seal the jar. What have you all had the best luck with? Am I better off purchasing seals to go over the rim of the jar? (I've read these work great for plastic but not as well for glass). I've read some people use teflon tape around the jar threads but I can't find a "clear" tape option online and any other color would look strange. Should I shrink wrap the entire jar? It's a unique shape so I'm unsure how viable this option is. Is there a more effective ice-pack option out there that won't cost too much. Sorry this post is so long but as you can tell, I'm extremely frustrated! :( I launched my business in March and it's been going SO well until now! I'm about ready to discontinuing my scrubs until the weather cools down but there's got to be a better way to do this!!! Thanks so much in advance for your help!!