Clematis query

I shall leave Guernsey Cream to her own devices and hope her buds don't get frosted like last year. I've managed to kill her brother living next door. No sign of life from Ernest Markham, it withered and died during late summer. I've left the place untouched just in  case it revives.

My Ernest Markham did the same in 2020. I thought it was quite dead, but up it came again last year - quite late - I think about May. I wondered if it was getting clematis wilt so I've shoveled a good depth of mulch around it this winter to bury its base deeper.

I've had it over 20 years and I grew it originally from a cutting, so I'll take some cuttings of it this year as a precaution.

Never had much luck taking clematis cuttings? What the trick?