I Have Been Told By My GP That I Have

I have been told by my GP that i have trigger finger. My centre finger was stuck rigid to my palm every morning. Now 2 fingers are affected but they are no longer locked to the palm but can't close to a fist , are rigid and stick. This is a problem in my job. What I want to know is what treatment there is. I was told injections but apparently only 2 injections are permitted. Is this correct? What can I do to prevent this worsening? thank you
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