CMS Payment and SMTP Fixes

I'm seeking a skilled developer to troubleshoot and fix several errors in my CMS PRO MANAGEMENT installation. I have full access to the source code and admin panel.

Key Tasks:
- Fix the STRIPE bug: payment link does not work (goes round in circles) + integrate payments into the database
- Fix the PayPal bug: payment is made correctly but not encoded in the database
- Fix the SMTP Mailer: enable sending emails from my Mailjet account in the CMS. Currently, the error message “Some of the emails could not be reached!” appears
- Fix a few other minor display bugs

Ideal skills and experience:
- Proficient in debugging CMS, especially payment integrations
- Experience with Stripe, PayPal, and SMTP mailers
- Strong problem-solving skills
- Familiarity with Mailjet and database integration