Modifying search criteria and searching from results page >1 persists pn parameter

[sarinapadilla]

Issue description

If a user selects to modify search criteria from a page number beyond the first page of results, and then performs a search with those new criteria, the pn parameter persists and will load the new results on that page number. This can result in the in the no trials page showing with the messaging of the page number being invalid, as the new search results may not display as many pages of results as the original search results.

ESTIMATE TBD

Steps to reproduce the issue

Page number persisting:

1. Go to https://www.cancer.gov/about-cancer/treatment/clinical-trials/search/r?a=15&loc=0&pn=10&rl=2
2. Click Modify Search Criteria
3. Enter 60 in the Age field
4. Click Find Trials
5. See that the parameter pn=5 is persisted in the URL

Page number persisting, and invalid search criteria page showing:

1. Go to https://www.cancer.gov/about-cancer/treatment/clinical-trials/search/r?a=30&loc=0&pn=7&rl=2
2. Click Modify Search Criteria
3. Select Acute Lymphoblastic Leukemia in the Primary Cancer Type/Condition field
4. Select B Acute Lymphoblastic Leukemia in the Subtype field
5. Select Recurrent B Acute Lymphoblastic Leukemia in the Stage field
6. Click Find Trials
7. See that the no trials page is displayed, with the message that "Page 7 is invalid"

What's the expected result?

• The search should restart at the first page of results

What's the actual result?

• The no trials page is displayed, with the message that "Page is invalid"

Additional details / screenshot

• ![Screenshot]()

Related Tickets

• Issue #9999
• Issue #9999