Error in ./prepare_requirements_ros1.sh

[CaesarCu]

I get the following error when the script attempts to contact a key server?

=> ERROR [10/20] RUN apt-key adv --keyserver hkps.pool.sks-keyservers.net --recv-keys 421C365BD9FF1F717815A3895523BAEEB01FA11 58.6s

[10/20] RUN apt-key adv --keyserver hkps.pool.sks-keyservers.net --recv-keys 421C365BD9FF1F717815A3895523BAEEB01FA116:
#13 0.375 Executing: /tmp/tmp.jh5pAdTiIx/gpg.1.sh --keyserver
#13 0.375 hkps.pool.sks-keyservers.net
#13 0.375 --recv-keys
#13 0.375 421C365BD9FF1F717815A3895523BAEEB01FA116
#13 0.377 gpg: requesting key B01FA116 from hkp server hkps.pool.sks-keyservers.net
#13 58.49 ?: hkps.pool.sks-keyservers.net: Host not found
#13 58.49 gpgkeys: HTTP fetch error 7: couldn't connect: Connection timed out
#13 58.49 gpg: no valid OpenPGP data found.
#13 58.49 gpg: Total number processed: 0
#13 58.49 gpg: keyserver communications error: keyserver unreachable
#13 58.49 gpg: keyserver communications error: public key not found
#13 58.49 gpg: keyserver receive failed: public key not found

---

executor failed running [/bin/sh -c apt-key adv --keyserver hkps.pool.sks-keyservers.net --recv-keys 421C365BD9FF1F717815A3895523BAEEB01FA116]: exit code: 2