after updating wordpress and a pluggin, the site is not working. Any idea?

Hello everyone. I am new with the templates. Just a quick question, please. I bought a template in Envato market 4 years ago, with the slideRevolution 5.1.6 pluggin. I updated to wordpress 5.5.3. at some point.
Now the pluggin is not working, nor the site, probably for one of the updates (not sure if because of the wordpress). It says that:

Fatal error: Uncaught Error: operator not supported for strings in /home/u917843485/domains/pablovelasco3d.com/public_html/wp-content/plugins/revslider/includes/framework/base-admin.class.php:71 Stack trace: #0 /home/u917843485/domains/pablovelasco3d.com/public_html/wp-content/plugins/revslider/admin/revslider-admin.class.php(465): RevSliderBaseAdmin::addMetaBox(‘Revolution Slid…’, ‘’, Array, NULL) #1 /home/u917843485/domains/pablovelasco3d.com/public_html/wp-content/plugins/revslider/admin/revslider-admin.class.php(72): RevSliderAdmin->addSliderMetaBox() #2 /home/u917843485/domains/pablovelasco3d.com/public_html/wp-content/plugins/revslider/admin/revslider-admin.class.php(44): RevSliderAdmin->init() #3 /home/u917843485/domains/pablovelasco3d.com/public_html/wp-content/plugins/revslider/revslider.php(165): RevSliderAdmin->__construct(’/home/u91784348…’) #4 /home/u917843485/domains/pablovelasco3d.com/public_html/wp-admin/includes/plugin.php(2255): include(’/home/u91784348…’) #5 /home/u917843485/domains/pablovelasc in /home/u917843485/domains/pablovelasco3d.com/public_html/wp-content/plugins/revslider/includes/framework/base-admin.class.php on line 71

Please, do you know if I should undone one of the updates for having the site working again?. It´s just a minute, I´m having big troubles for this, and I have no knowledge in web design unfortunately.
Thank you very much for your time

Hi,

May be compatibility issues. Please make sure you are using the latest version theme, Slider Revolution plugin and your server php version is uptodate.

If the above things not solved please contact your purchased theme author, theme author will assist you.

How to contact an author to get support or for any technical query:

Thanks

Hi @pablovelasco3d,

Thanks for using Slider Revolution. I noticed that you’re still using a very old version of the Slider Revolution Plugin. Please update it to v6.2.23 and it should fix the issues you had there. If you need further assistance, you can email us at help@themepunch.support

Thanks!

KC
ThemePunch