I modified the prior for cut-points to (0,5) and reran the syntax and it worked well with reasonable Rhat and convergence.
Group-Level Effects:
~idno (Number of levels: 898)
Estimate Est.Error l-95% CI u-95% CI Rhat Bulk_ESS Tail_ESS
sd(Intercept) 4.32 0.15 4.04 4.62 1.00 711 1152
Population-Level Effects:
Estimate Est.Error l-95% CI u-95% CI Rhat Bulk_ESS Tail_ESS
Intercept[1] -11.74 0.54 -12.87 -10.72 1.00 1560 2403
Intercept[2] -8.35 0.31 -8.97 -7.74 1.00 1307 2258
Intercept[3] -5.80 0.23 -6.25 -5.36 1.00 859 1851
Intercept[4] -3.61 0.19 -3.98 -3.23 1.01 639 1427
Intercept[5] -1.81 0.18 -2.16 -1.46 1.01 560 1154
Intercept[6] -0.01 0.17 -0.34 0.33 1.01 528 1297
Intercept[7] 1.50 0.17 1.17 1.85 1.01 529 1133
Intercept[8] 3.12 0.18 2.78 3.49 1.01 578 1077
Intercept[9] 4.70 0.20 4.32 5.08 1.01 677 1627
Intercept[10] 6.25 0.22 5.82 6.69 1.01 830 1734
Intercept[11] 7.98 0.26 7.48 8.50 1.01 1071 2221
Intercept[12] 10.02 0.33 9.38 10.67 1.00 1736 2649
Intercept[13] 12.00 0.45 11.16 12.90 1.00 2733 2877
Intercept[14] 14.64 0.87 13.10 16.56 1.00 4483 2673
mochf 0.52 0.08 0.35 0.68 1.00 2247 2494
Simplex Parameters:
Estimate Est.Error l-95% CI u-95% CI Rhat Bulk_ESS Tail_ESS
mochf1[1] 0.17 0.09 0.03 0.36 1.00 3518 3121
mochf1[2] 0.83 0.09 0.64 0.97 1.00 3518 3121
Thanks for your help and guidance,