Getting access denied error for storegateway container

[Preeti0512]

I have upgraded thanos from v0.18.0 to v0.30.0, but on updating everything works fine except for storegateway containers. They are giving me access denied error for the s3 bucket. But it is working perfectly for v0.18.0 version.
Error from container:
err="Access Denied\nBaseFetcher: iter bucket\ngithub.com/thanos-io/thanos/pkg/block.(*BaseFetcher).fetchMetadata\n\t/app/pkg/block/fetcher.go:383\ngithub.com/thanos-io/thanos/pkg/block.(*BaseFetcher).fetch.func2\n\t/app/pkg/block/fetcher.go:447\ngithub.com/golang/groupcache/singleflight.(*Group).Do\n\t/go/pkg/mod/github.com/golang/[email protected]/singleflight/singleflight.go:56\ngithub.com/thanos-io/thanos/pkg/block.(*BaseFetcher).fetch\n\t/app/pkg/block/fetcher.go:445\ngithub.com /thanos-io/thanos/pkg/block.(*MetaFetcher).Fetch\n\t/app/pkg/block/fetcher.go:505\ngithub.com/thanos-io/thanos/pkg/store.(*BucketStore).SyncBlocks\n\t/app/pkg/store/bucket.go:521\ngithub.com/thanos-io/thanos/pkg/store.(*BucketStore).InitialSync\n\t/app/pkg/store/bucket.go:590\nmain.runStore.func3\n\t/app/cmd/thanos/store.go:384\ngithub.com/oklog/run.(*Group).Run.func1\n\t/go/pkg/mod/github.com/oklog/[email protected]/group.go:38\nruntime.goexit\n\t/usr/local/go/src/runtime/asm_amd64.s:1594\nsync block\ngithub.com/thanos-io/thanos/pkg/store.(*BucketStore).InitialSync\n\t/app/pkg/store/bucket.go:591\nmain.runStore.func3\n\t/app/cmd/thanos/store.go:384\ngithub.com/oklog/run.(*Group).Run.func1\n\t/go/pkg/mod/github.com/oklog/[email protected]/group.go:38\nruntime.goexit\n\t/usr/local/go/src/runtime/asm_amd64.s:1594\nbucket store initial sync\nmain.runStore.func3\n\t/app/cmd/thanos/store.go:386\ngithub.com/oklog/run.(*Group).Run.func1\n\t/go/pkg/mod/github.com/oklog/[email protected]/group.go:38\nruntime.goexit\n\t/usr/local/ go/src/runtime/asm_amd64.s:1594\nstore command failed\nmain.main\n\t/app/cmd/thanos/main.go:161\nruntime.main\n\t/usr/local/go/src/runtime/proc.go:250\nruntime.goexit\n\t/usr/local/go/src/runtime/asm_amd64.s:1594"

could some1 please help me what could be the issue?