That cover ain't shifting. I have already bent it. Keep going?
Could just be seized with crap. Have you tried spraying some WD40, or similar, in the gaps and leaving it for a while*.
(*I realise this is the bike equivalent to an IT help desk's 'have you turned it off and on again')
(*I realise this is the bike equivalent to an IT help desk's 'have you turned it off and on again')