And the straps are nowhere near tight enough. Join “UK car seat safety” on Facebook for guidance
Is it the Cybex one? Are the newborn inserts in?
You need to lower the headrest to the lowest setting, put any newborn inserts in and replace the shoulder pads with the proper ones. This won't contain him in a crash.
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Your straps look way too high, they should be coming from just below baby’s shoulders. Can you rethread them lower at the back ?