Hmm, is it just since the latest lockdown? Is it possible that you could have
that virus ? Illness will push your need for insulin up drastically.
Some possible reasons for raised levels
1) illness
2) stress
3) reduced exercise
4) problems with insulin and/or injection pens (eg change insulin vials and check your pens are working correctly)
5) overused injection sites (though seems unlikely that this would lead to consistently raised levels).
6) medication eg steroids
Are you checking for ketones? DKA is a concern with persistent high levels and you should definitely call 111 if you think it might be an issue.
There is a UK helpline for T1 diabetics which might be helpful to you
0345 123 2399
open mon-fri 9am to 6pm.
If your levels are due to illness then you can follow sick day rules
Layout 1 (northumbria.nhs.uk)
Have you tried applying correction doses? Are you able to contact your diabetic team by phone or email? If at all possible, you should be getting medical advice on this, rather than just getting some suggestions on a forum.
Good luck.