What should the tension on a Janome MyStyle 22 be, please?

Free manual, possibly yours.

https://www.manualslib.com/manual/720972/Janome-Mystyle-100.html


Janome MyStyle 100 Instruciton Manual

It may be in the buttonhole mode, change the stitch selector to straight stitch.

try these sites,, call them or email about a manual
sewvacdoctor.com
a1sewingmachines.com

it's possible that the tension dial needs to be replaced

Try a ball point needle which is for stretch fabrics. Using the wrong needle can cause skipped stitches.

http://www.sewon.info/downloads/NEWHOME-652.html

Unfortunately Janome don't provide links to their user manuals, so the only option is to buy one. I cannot find any free examples elsewhere, but this supplier has what you need at a reasonable price. If you find that you cannot eventually get the tension correct, then your machine is worn or out of adjustment and will need servicing. A smooth running machine is vital for consistent tension, so make sure that you have cleaned out the lint from the mechanism and applied sewing machine oil as advised in the owners manual.

Hope that I've been of some assistance and that you quickly solve your tension teaser! Please take a moment to rate my reply.

I found one site that listed a manual for $19.80, but you may have better luck in contacting Janome - http://janome.com/index.cfm/ContactUs/General_Inquiries

just visit www.janomestuff.com to avail a new Pdf for your sewing machine.