I have encountered this before. When a base is built in Tower Entre-deux the antenna cannot be dismantled and the base cannot be dismantled either.

HQC are three different scenarios, and IGLA is cover name used in all of them, screenshots are unusable for us

It's Everon HQC

This still does not help us.

IGLA codename is used by USSR faction, and it comes from a pool of codenames used for prespawned and player made bases as well.
Please make a proper distinction between player built and pre-spawned and if it is pre spawned - provide actual name of the base written above the codename in smaller letters.
If it is a player built base the issue might be deeper than the information you have provided so far

https://report.bistudio.com/issues/AREXP-242?commentId=69ff1ba4c8d409c6f0c85831

It seems like the problem has already been described here.

If a base is built close to tower entre-deux or tower regina relays, and an antenna is placed there, such antenna cannot be dismantled, which makes it impossible to dismantle and remove the whole base. This is confirmed.