Ucas tariff points

I have got 18 btec points on my BTEC extended Diploma Art and Design on my first year which as a merit. I got 12 BTEC points in my first assignment second year . On my last assignment I got 39 points DDMDM . I have added all my points up and got 69 btec points. My tutor said that MMM is 50/58 .
What is 69 btec points in tariff points?

I have got 18 btec points on my BTEC extended Diploma Art and Design on my first year which as a merit. I got 12 BTEC points in my first assignment second year . On my last assignment I got 39 points DDMDM . I have added all my points up and got 69 btec points. My tutor said that MMM is 50/58 .
What is 69 btec points in tariff points?

The last time you posted that image (on this thread) I came to the conclusion that you were studying the "Pearson BTEC Level 3 National Extended Diploma in Art and Design Practice" (2019) rather than the "Pearson BTEC Level 3 National Extended Diploma in Art and Design" (2016) which @bamtutor has linked to above. I reached that conclusion based upon the "MMM is 50 - 58" in the note from your tutor, which aligns with the 2019 qualification:

If you have indeed got a total of 69 BTEC points then you have a DDM according to the image above (from the specification). DDM is 128 UCAS points.
Note, however, that to leap from 18 BTEC points after year 1 to 69 BTEC points after year 2 would be unusual. So, as @bamtutor has suggested, it'd be safer if you could (a) confirm the exact name of the course you're studying and then (b) list every unit number / name / grade / mark / whatever you have.