Can someone tell me, what should I do in this situation?

First, restart R and confirm that the model ran

```
summary(model)
```

If so, model is class(lm) and `ols_vif_tol(model)`

should run.

still the same, i can't run the data on ols_vif_tol(model)

Error in str2lang(x) : attempt to use zero-length variable name

am i wrong somewhere?

Try running the example

```
# model
model <- lm(mpg ~ disp + hp + wt + drat, data = mtcars)
# vif and tolerance
ols_vif_tol(model)
```

in a fresh R session. You should get

```
suppressPackageStartupMessages({
library(olsrr)
})
# model
model <- lm(mpg ~ disp + hp + wt + drat, data = mtcars)
# vif and tolerance
ols_vif_tol(model)
#> Variables Tolerance VIF
#> 1 disp 0.1218116 8.209402
#> 2 hp 0.3454979 2.894373
#> 3 wt 0.1962092 5.096601
#> 4 drat 0.4386836 2.279547
```

^{Created on 2021-01-02 by the reprex package (v0.3.0.9001)}

If not, `olsrr`

may be corrupt and I'd try re-installing it.