Swiftkey acting strangely

I'm using Swiftkey for IOS12.1 on iPhone 8+ and the keyboard started acting strange from like 2 weeks ago: space after word not working and the words end up "glued" together. Even pressing space bar seems to take a while to introduce the space. 

Also, the keyboard have a "heavy" feeling to use with lag and unpredictable behaviour (such us inserting other words than intended). Is there any bug or it's my phone? I tried soft reset, works for a while but came back. One short term fix is to change keyboards, works fine for a while but gets back to the erratic behaviour after couple of minutes.