warning message when using metaSEM

We want to use metaSEM to conduct a mediation model based on four samples using TSSEM. There was a warning message in the summary of the output from the tssem1 function. The following is the R script we used to run the analysis:

Insert correlation matrices

M2_Study_2a <- data.matrix(data.frame(
IV = c(1, 0.236, 0.360),
M = c(0.236, 1, 0.247),
DV = c(0.360, 0.247, 1)
))

M2_Study_2b <- data.matrix(data.frame(
IV = c(1, 0.203, 0.207),
M = c(0.203, 1, 0.174),
DV = c(0.207, 0.174, 1)
))

M2_Study_3 <- data.matrix(data.frame(
IV = c(1, 0.153, 0.439),
M = c(0.153, 1, 0.203),
DV = c(0.439, 0.203, 1)
))

M2_Study_4 <- data.matrix(data.frame(
IV = c(1, 0.198, 0.327),
M = c(0.198, 1, 0.238),
DV = c(0.327, 0.238, 1)
))

Insert sample sizes information

N_Study_2a <- 198
N_Study_2b <- 200
N_Study_3 <- 278
N_Study_4 <- 296

Complie the data list

N_M2 <- c(N_Study_2a, N_Study_2b, N_Study_3, N_Study_4)
Cor_Matrix_M2 <- list(M2_Study_2a, M2_Study_2b, M2_Study_3, M2_Study_4)
Cor_Matrix_M2 <- lapply(Cor_Matrix_M2, function(x) {
dimnames(x) <- list(c("IV","M","DV"), c("IV","M","DV"))
x})
Data_M2 <- list(Cor_Matrix_M2, N_M2)
names(Data_M2) <- c("data", "n")
names(Data_M2$data) <- c("Study_2a", "Study_2b", "Study_3", "Study_4")

Proposed model in lavaan syntax

Mediation_Model <- "DV ~ cIV + bM
M ~ aIV
IV ~~ 1IV"
plot(Mediation_Model)

obs.vars1 <- as.character(c("IV","M","DV"))

Convert the lavaan syntax to RAM specification used in metaSEM

RAM <- lavaan2RAM(Mediation_Model, obs.variables=obs.vars1)

Random-effects model

Random_M2 <- tssem1(Data_M2$data, Data_M2$n, method="REM")
summary(Random_M2)

Then the warning message came up: "Warning: OpenMx status1 is neither 0 or 1. You are advised to 'rerun' it again."
The estimation of the first and third heterogeneity components also seems incorrect because there are NAs, for example, for Std.Error.
Any help would be greatly appreciated!