Error On instalation

Hi!
When I install the plugin a general error appears.
When I check the log I see this message:

2020/07/31 02:54:34 [error] 1883#0: *155 FastCGI sent in stderr: “PHP message: PHP Fatal error: Uncaught Error: Call to undefined method WooCommerce::is_rest_api_request() in /usr/share/nginx/woocommerce34/wp-content/plugins/wepos/wepos.php:391
Stack trace:
#0 /usr/share/nginx/woocommerce34/wp-includes/class-wp-hook.php(287): We_POS->on_wc_init(”)
#1 /usr/share/nginx/woocommerce34/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(”, Array)
#2 /usr/share/nginx/woocommerce34/wp-includes/plugin.php(478): WP_Hook->do_action(Array)
#3 /usr/share/nginx/woocommerce34/wp-content/plugins/woocommerce/includes/class-woocommerce.php(489): do_action(‘woocommerce_ini…’)
#4 /usr/share/nginx/woocommerce34/wp-includes/class-wp-hook.php(287): WooCommerce->init(”)
#5 /usr/share/nginx/woocommerce34/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(NULL, Array)
#6 /usr/share/nginx/woocommerce34/wp-includes/plugin.php(478): WP_Hook->do_action(Array)
#7 /usr/share/nginx/woocommerce34/wp-settings.php(540): do_action(‘init’)
#8 /usr/share/nginx/woocommerce34/wp-config.ph” while reading response header from upstream, client: 161.35.134.253, server: https://www.woo34.solve-key.com.ar, request: “GET /wp-json/wc/v2/orders?after=2020-07-30T14%3A50%3A35&page=1&per_page=50&orderby=date&order=asc&consumer_key=&consumer_secret=HTTP/1.1”, upstream: “fastcgi://unix:/var/run/php-fpm/php-fpm.sock:”, host: “www.woo34.solve-key.com.ar.”

The plugin looks awesome, so I wanted to give it a try

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