Hi! My 7 week old baby is ending up sideways in his Il Tutto Cozee Breeze bassinet. He manages to wriggle his way around and is often ending up wedged up at the side. The bassinet is only mesh long ways. The short sides are not mesh. He sleeps in a sleep suit either the love to dream swaddle or the ergo pouch. Any advice please ? Thank you

Many babies do wriggle & squirm & can be quite active.
Its not necessarily about stopping this but ensuring the environment remains safe.
Sometimes it is because they like hands free to touch their face or suck on fingers.
The products you describe are both forms of swaddling/wrapping (swaddle suits) with their arms inside.

Are you able to try him with his arms out?
Are you using any bedding (sheets or blankets) in bassinet?
You could try moving your baby to a cot with more space.

Your baby may soon be attempting to roll.
Most babies are rolling from 4-5 months - some earlier, some later.
If this is happening he will need to be moved to his cot & have his arms free.
Babies need the space of a cot & arms free to roll well.
https://rednose.org.au/article/what-do-we-do-now-that-a-baby-has-started-to-roll-over

How does he go with tummy time when awake?