02-15-2019 03:57 PM
Ok, so I was browsing the Play Store trying to find and possibly reproduce your issue. I found Smart Launcher Pro 3, which I should note, hasn't been updated since March 16th, 2018. I also found Smart Launcher 5 by the same Developer, and was last updated January 25th, 2019.
Can you verify that using the stock (default) Launcher doesn't cause the same behavior? Meaning, are you able to successfully add a 1x1 widget to your homescreen using the stock Launcher? Being that SLP3 is quite outdated, I wouldn't be surprised if you switch over to the stock Launcher and find that 1x1 widget already there. I've seen this happen before.