How do I join polyester tubular yarn skeins together? I'm working on a moss stitch knit baby blanket with Hobbycraft's In The Zone tubular yarn, which is 100% polyester. I've come to the end of my first skein and I'm struggling to figure the best way to join the strands together to continue my work so it doesn't create a bump from a knot.

I usually use the Invisible knot technique with regular fibre yarn, but because this yarn isn't "yarn" in the traditional sense, tying it together in this way still creates a knot which would be noticeable in a knitted blanket (I find them easier to hide in crocheting).

I've scoured YouTube and tried a method for tubular/tape yarn, but because this stuff has kind of a poly filling in it, this method didn't work either.

The photo has a diagonal cross-section of the end of a strand so you can get an idea of its composition. I would be grateful for any advice on this! =)
So, in the meantime, I'm trying something a bit different... It's not the neatest sewing job, but I've managed to sew the strands together, doing a basic up and down through the middle (with the strands overlapping each other) and then looping over and under each side to hold it together on the sides as well. At least this way, there's no big knot and it feels pretty sturdy. ‍♀️


Here's one side of what it looks like worked in with a few rows done extra...

 
And here's the other side of the work. Maybe in future, I will sew together a smaller section and snip the excess, as even though the bit I sewed was only about 1cm, it's still a bit noticeable... Though probably still less so than if it was knotted. I'll try to do maybe half a cm next time (tricky!) and if I succeed, I will post back again! In the meantime, if anyone else has any other suggestions, I will gladly receive them! =)