Error while defining restriction matrix using var::makeHypothesis estimating a SUR with systemfit

Question

I am trying to estimate a system of seemingly unrelated equations using the systemfit package. There seems to be an issue with building the restriction matrix. Upon running the systemfit function step-by-step, I obtain an error when executing this command:

R.restr <- car::makeHypothesis(coefNamesModReg, restrict.matrix, restrict.rhs)

! error in constants(lhs, cnames_symb) : The hypothesis "eq1_I(cdf1 * np2)-eq2_I(cdf2 * np1)=0" is not well formed: contains bad coefficient/variable names. In addition: Warning message: In constants(lhs, cnames_symb) : NAs introduced through coercion.

coefNamesModReg is a vector chr [1:645]; restrict.matrix is a vector chr [1:210]; restrict.rhs is set to NULL.

The error returns the first element of restrict matrix. I am new to this type of models, so I am at a loss at where a potential error could be. Is it a problem with variable names, dimensions or did I define the restrict.matrix incorrectly?

Here is a reproducible example:

library(car)

restrict.matrix <- c(
  "eq1_I(cdf1 * np2)-eq2_I(cdf2 * np1)=0",
  "eq1_I(cdf1 * np3)-eq3_I(cdf3 * np1)=0",
  "eq1_I(cdf1 * np4)-eq4_I(cdf4 * np1)=0",
  "eq1_I(cdf1 * np5)-eq5_I(cdf5 * np1)=0",
  "eq1_I(cdf1 * np6)-eq6_I(cdf6 * np1)=0",
  "eq1_I(cdf1 * np7)-eq7_I(cdf7 * np1)=0",
  "eq1_I(cdf1 * np8)-eq8_I(cdf8 * np1)=0",
  "eq1_I(cdf1 * np9)-eq9_I(cdf9 * np1)=0",
  "eq1_I(cdf1 * np10)-eq10_I(cdf10 * np1)=0",
  "eq1_I(cdf1 * np11)-eq11_I(cdf11 * np1)=0")

coefNamesModReg <- c(
  "cdf1",
  "I(cdf1 * y1)",
  "I(cdf1 * y2)",
  "I(cdf1 * y3)",
  "I(cdf1 * y4)",
  "I(cdf1 * y5)",
  "I(cdf1 * z1)",
  "I(cdf1 * z2)",
  "I(cdf1 * z3)",
  "I(cdf1 * yz1)")

restrict.rhs <- NULL

R.restr <- car::makeHypothesis(coefNamesModReg, restrict.matrix, restrict.rhs)