How to change the assigned colors to each cluster in seurat object.

library(biomaRt)
library(knitr)
library(tidyverse)
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## x dplyr::filter() masks stats::filter()
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library(dplyr)
library(Seurat)
## Attaching SeuratObject
library(SeuratWrappers)
library(ggplot2)
library(clustifyr)
library(RColorBrewer)
library(gprofiler2)
library(scales)
## 
## Attaching package: 'scales'
## The following object is masked from 'package:purrr':
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##     discard
## The following object is masked from 'package:readr':
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##     col_factor
library(ggpubr)
library(jpeg)
pbmc <- readRDS("/mnt/nectar_volume/home/eraz0001/KELLY 2020/E11.5/Final_15_clusters.RDS")
pbmc
## An object of class Seurat 
## 16968 features across 2333 samples within 1 assay 
## Active assay: RNA (16968 features, 2000 variable features)
##  2 dimensional reductions calculated: pca, umap
#new cluster names/IDs
current.cluster.ids <- c(0:6)
new.cluster.ids <- c("DCh", "Osteocytes", "Osteoblasts", "HtCh", "Endothelial Cells", "Hoxd13+", "Chondrocytes")
pbmc@meta.data$celltype <- plyr::mapvalues(x = pbmc@meta.data[,"seurat_clusters"], from = current.cluster.ids, to = new.cluster.ids)
head(pbmc)
level.pbmc <- c("DCh", "Osteocytes", "Osteoblasts", "HtCh", "Endothelial Cells", "Hoxd13+", "Chondrocytes")
pbmc$seurat_clusters <- factor(pbmc$seurat_clusters, levels = level.pbmc)
palette.pbmc <- c("#b30024",  "#e31a1c",      "#ff7f00",            "#08519c", "#762a83",  "#f28ac6", "#20b2aa")
show_col(palette.pbmc)

ax<- DimPlot(pbmc, cols = palette.pbmc)