There must be some underlying PHP error here.
Try to remove those custom shortcodes, and all other content from the post – then save again.
If it works, try to add the custom things again one by one and save agin each time, check when the issue comes back, and then debug that code of the shortcode that you just added prior to the failure.
If that doesn’t help, try to log errors using https://codex.www.ads-software.com/WP_DEBUG, and save again, then check the error logs to see if you can see any obvious error logged just after you save the post.
Again if that does not help a test can be to disable plugins one by one and check when things start to work again (the same can be done with the theme). This could show potential conflicts with some plugin, which then eventually would have to be reported to that plugin.
Let me know if you can spot some error in the logs – I can also take a look at it and maybe point to the issue causing it.