I just changed mine this morning too. My wife noticed it wasn't working right. There was dried battery acid all over the compartment so I had to clean everything out and put fresh batteries in. Congrats on the weight loss.
FUNNY story: This morning I realized my weight wasn't actually stalling or going up, thank goodness. The smart scale was low on power and feeding me bad numbers. Once I swapped the battery it showed I had hit my first goal at 140 pounds and I'm actually at 138 now. I've restarted intermittent fasting too so overall I've dropped close to 20 pounds. Always check those batteries. To treat myself I did some pep shopping and I'm adding a few new items to the stack. Can't wait for them to show up. PS: cross posted on my intro post.