I don’t know if it’ll work for you, but my technique for hard-to-pronounce foreign languages where I can manage to pronounce individual syllables but not full words, has been to do slow pronunciation drills, working backwards from the end of the word – for example

Rès, rès, rès, rès

Grès, grès, grès, grès

Ogrès, ogrès, ogrès, ogrès

Rogrès, rogrès, rogrès, rogrès

Progrès, progrès, progrès, progrès

Le progrès, le progrès, le progrès, le progrès

Maybe try this out, walking your way up the word very slowly, and see if it works? Hope this helps, and if it works let us know how it goes!