Unable to install slack notification plugin(https://plugins.jenkins.io/slack/) for jenkins 2.401.1

Jenkins setup:
Jenkins: 2.401.1
OS: Linux - 5.15.0-1036-aws
Java: 11.0.21 - Ubuntu (OpenJDK 64-Bit Server VM)

amazon-ecs:1.48
ant:497.v94e7d9fffa_b_9
antisamy-markup-formatter:159.v25b_c67cd35fb_
apache-httpcomponents-client-4-api:4.5.14-150.v7a_b_9d17134a_5
aws-credentials:191.vcb_f183ce58b_9
aws-java-sdk-ec2:1.12.481-392.v8b_291cfcda_09
aws-java-sdk-ecs:1.12.481-392.v8b_291cfcda_09
aws-java-sdk-efs:1.12.481-392.v8b_291cfcda_09
aws-java-sdk-minimal:1.12.481-392.v8b_291cfcda_09
bootstrap5-api:5.3.0-1
bouncycastle-api:2.29
branch-api:2.1122.v09cb_8ea_8a_724
build-notifications:1.5.0
build-timeout:1.31
caffeine-api:3.1.8-133.v17b_1ff2e0599
checks-api:2.0.0
cloudbees-folder:6.815.v0dd5a_cb_40e0e
command-launcher:107.v773860566e2e
commons-httpclient3-api:3.1-3
commons-lang3-api:3.12.0-36.vd97de6465d5b_
commons-text-api:1.10.0-36.vc008c8fcda_7b_
credentials:1271.v54b_1c2c6388a_
credentials-binding:631.v861c06d062b_4
display-url-api:2.3.7
durable-task:513.vc48a_a_075a_d93
echarts-api:5.4.0-5
email-ext:2.100
font-awesome-api:6.4.0-2
git:5.2.0
git-client:4.4.0
github:1.37.1
github-api:1.314-431.v78d72a_3fe4c3
github-branch-source:1728.v859147241f49
global-slack-notifier:1.5
gradle:2.8.2
instance-identity:173.va_37c494ec4e5
ionicons-api:56.v1b_1c8c49374e
jackson2-api:2.15.2-350.v0c2f3f8fc595
jakarta-activation-api:2.0.1-3
jakarta-mail-api:2.0.1-3
javax-activation-api:1.2.0-6
javax-mail-api:1.6.2-9
jaxb:2.3.8-1
jdk-tool:73.vddf737284550
jjwt-api:0.11.5-77.v646c772fddb_0
jobConfigHistory:1229.v3039470161a_d
jquery3-api:3.7.0-1
junit:1217.v4297208a_a_b_ce
ldap:682.v7b_544c9d1512
mailer:457.v3f72cb_e015e5
matrix-auth:3.1.10
matrix-project:789.v57a_725b_63c79
mina-sshd-api-common:2.10.0-69.v28e3e36d18eb_
mina-sshd-api-core:2.10.0-69.v28e3e36d18eb_
miniorange-saml-sp:2.3.1
notify-events:1.6.2
okhttp-api:4.11.0-145.vcb_8de402ef81
pam-auth:1.10
pipeline-build-step:505.v5f0844d8d126
pipeline-github-lib:42.v0739460cda_c4
pipeline-graph-analysis:202.va_d268e64deb_3
pipeline-groovy-lib:656.va_a_ceeb_6ffb_f7
pipeline-input-step:468.va_5db_051498a_4
pipeline-milestone-step:111.v449306f708b_7
pipeline-model-api:2.2144.v077a_d1928a_40
pipeline-model-definition:2.2144.v077a_d1928a_40
pipeline-model-extensions:2.2144.v077a_d1928a_40
pipeline-rest-api:2.33
pipeline-stage-step:305.ve96d0205c1c6
pipeline-stage-tags-metadata:2.2144.v077a_d1928a_40
pipeline-stage-view:2.33
plain-credentials:143.v1b_df8b_d3b_e48
plugin-util-api:3.3.0
rebuild:330.v645b_7df10e2a_
resource-disposer:0.22
role-strategy:689.v731678c3e0eb_
saml:4.418.vdfa_7489a_b_a_2d
scm-api:676.v886669a_199a_a_
script-security:1294.v99333c047434
slack:684.v833089650554
snakeyaml-api:1.33-95.va_b_a_e3e47b_fa_4
ssh-credentials:305.v8f4381501156
ssh-slaves:2.877.v365f5eb_a_b_eec
sshd:3.303.vefc7119b_ec23
structs:324.va_f5d6774f3a_d
timestamper:1.25
token-macro:359.vb_cde11682e0c
trilead-api:2.84.v72119de229b_7
variant:59.vf075fe829ccb
workflow-aggregator:596.v8c21c963d92d
workflow-api:1251.vd4889a_b_0a_065
workflow-basic-steps:1017.vb_45b_302f0cea_
workflow-cps:3726.v83f8cff396c9
workflow-durable-task-step:1278.v94b_dc2b_50c6f
workflow-job:1316.vd2290d3341a_f
workflow-multibranch:756.v891d88f2cd46
workflow-scm-step:415.v434365564324
workflow-step-api:639.v6eca_cd8c04a_a_
workflow-support:848.v5a_383b_d14921
ws-cleanup:0.45

The plugin is already installed.